{"id":21891,"date":"2026-10-11T17:50:27","date_gmt":"2026-10-11T09:50:27","guid":{"rendered":"https:\/\/synopower.club\/?post_type=docs&#038;p=21891"},"modified":"2026-10-11T18:06:54","modified_gmt":"2026-10-11T10:06:54","password":"","slug":"synology-mailplus-smtp-relay-resend","status":"publish","type":"docs","link":"https:\/\/synopower.club\/ja\/docs\/synology-mailplus-smtp-relay-resend\/","title":{"rendered":"Synology MailPlus SMTP\u30ea\u30ec\u30fc\uff1a\u518d\u9001\u4fe1\u306b\u3088\u308b\u62d2\u5426\u30e1\u30fc\u30eb\u306e\u4fee\u6b63"},"content":{"rendered":"<p class=\"wp-block-paragraph\">SMTP\u30ea\u30ec\u30fc\u306f\u3001\u3042\u306a\u305f\u306b\u4ee3\u308f\u3063\u3066\u30e1\u30c3\u30bb\u30fc\u30b8\u3092\u9001\u4fe1\u3059\u308b2\u756a\u76ee\u306e\u30e1\u30fc\u30eb\u30b5\u30fc\u30d0\u30fc\u3067\u3042\u308a\u3001\u53d7\u4fe1\u5074\u306f\u3042\u306a\u305f\u306e\u8a55\u5224\u3067\u306f\u306a\u304f\u3001\u305d\u306e\u30b5\u30fc\u30d0\u30fc\u306e\u8a55\u5224\u3092\u5224\u65ad\u3057\u307e\u3059\u30022026\u5e7410\u67089\u65e5\u3001\u79c1\u305f\u3061\u306f\u6025\u3044\u3067\u305d\u308c\u304c\u5fc5\u8981\u3067\u3057\u305f\u3002SynoPower Club\u306f\u5b8c\u5168\u306bSynology\u4e0a\u3067\u52d5\u4f5c\u3057\u3001\u3059\u3079\u3066\u306e\u6ce8\u6587\u78ba\u8a8d\u3068\u30e9\u30a4\u30bb\u30f3\u30b9\u30ad\u30fc\u306fSynology MailPlus\u3092\u7d4c\u7531\u3057\u3066\u9001\u4fe1\u3055\u308c\u307e\u3059\u3002\u305d\u306e\u6669\u3001\u30d9\u30eb\u30ae\u30fc\u306e\u9867\u5ba2\u304c\u30e9\u30a4\u30bb\u30f3\u30b9\u306e\u652f\u6255\u3044\u3092\u884c\u3044\u3001\u30ad\u30fc\u3092\u542b\u3080\u30e1\u30fc\u30eb\u304c\u3059\u3050\u306b\u8fd4\u9001\u3055\u308c\u3066\u304d\u307e\u3057\u305f\u3002 <code>552 5.2.0 \u3042\u306a\u305f\u306e\u30e1\u30c3\u30bb\u30fc\u30b8\u306f\u30b9\u30d1\u30e0\u3068\u307f\u306a\u3055\u308c\u307e\u3059<\/code>SPF\u3001DKIM\u3001DMARC\u306f\u3059\u3079\u3066\u5408\u683c\u3057\u3066\u3044\u307e\u3057\u305f\u3002\u3053\u306eNAS\u30db\u30b9\u30c6\u30a3\u30f3\u30b0101\u306e\u8a18\u4e8b\u3067\u306f\u3001\u62d2\u5426\u3059\u308b\u53d7\u4fe1\u8005\u30c9\u30e1\u30a4\u30f3\u306e\u307f\u306b\u5bfe\u3057\u3066Resend\u3092SMTP\u30ea\u30ec\u30fc\u3068\u3057\u3066\u8ffd\u52a0\u3059\u308b\u65b9\u6cd5\u3001\u5fc5\u8981\u306a\u30ec\u30b3\u30fc\u30c9\u3001\u30c6\u30b9\u30c8\u65b9\u6cd5\u3001\u304a\u3088\u3073\u30b5\u30fc\u30d3\u30b9\u304c\u30e1\u30c3\u30bb\u30fc\u30b8\u5185\u3067\u9759\u304b\u306b\u5909\u66f4\u3059\u308b\u5185\u5bb9\u306b\u3064\u3044\u3066\u8aac\u660e\u3057\u307e\u3059\u3002<\/p>\n\n\n\n<blockquote class=\"wp-block-quote is-layout-flow wp-block-quote-is-layout-flow\">\n<p class=\"wp-block-paragraph\"><strong>SynoPower Club\u30dd\u30a4\u30f3\u30c8\uff1a<\/strong> \u79c1\u306fSynology\u306e\u30b5\u30dd\u30fc\u30c8\u90e8\u9580\u3067\u9577\u5e74\u50cd\u3044\u3066\u3044\u307e\u3057\u305f\u304c\u3001\u30e1\u30fc\u30eb\u914d\u4fe1\u306e\u4e0d\u78ba\u5b9f\u6027\u304c\u3001\u307b\u3068\u3093\u3069\u306e\u4eba\u304c\u81ea\u793e\u30e1\u30fc\u30eb\u306e\u904b\u7528\u3092\u8ae6\u3081\u308b\u7406\u7531\u3067\u3057\u305f\u3002\u5f7c\u3089\u306f\u3001\u3059\u3079\u3066\u306e\u30e1\u30fc\u30eb\u30dc\u30c3\u30af\u30b9\u3092\u30db\u30b9\u30c6\u30a3\u30f3\u30b0\u30b9\u30a4\u30fc\u30c8\u306b\u79fb\u884c\u3059\u308c\u3070\u89e3\u6c7a\u3059\u308b\u3068\u8003\u3048\u3066\u3044\u307e\u3057\u305f\u304c\u3001\u5b9f\u969b\u306b\u306f\u305d\u3046\u3067\u306a\u3044\u5834\u5408\u304c\u307b\u3068\u3093\u3069\u3067\u3059\u3002\u79c1\u305f\u3061\u306e\u5834\u5408\u306f\u3001\u30e1\u30fc\u30eb\u30b5\u30fc\u30d0\u30fc\u306f\u6b63\u5e38\u3067\u3001DNS\u3082\u6b63\u3057\u304f\u3001\u9001\u4fe1\u7d4c\u8def\u4e0a\u306e\u305f\u3063\u305f1\u3064\u306e\u30db\u30c3\u30d7\u306b\u3001\u4e00\u90e8\u306e\u53b3\u683c\u306a\u30d7\u30ed\u30d0\u30a4\u30c0\u30fc\u306b\u5bfe\u3057\u3066\u4e0d\u9069\u5207\u306a\u540d\u524d\u304c\u4ed8\u3051\u3089\u308c\u3066\u3044\u305f\u3060\u3051\u3067\u3057\u305f\u3002Synology MailPlus\u3067\u306f\u3001\u305d\u306e1\u3064\u306e\u30db\u30c3\u30d7\u3092\u3001\u8a72\u5f53\u3059\u308b\u30d7\u30ed\u30d0\u30a4\u30c0\u30fc\u306b\u5bfe\u3057\u3066\u306e\u307f\u5909\u66f4\u3059\u308b\u3053\u3068\u304c\u3067\u304d\u3001\u30eb\u30fc\u30eb\u306e\u4f5c\u6210\u306b\u306f\u308f\u305a\u304b10\u5206\u3057\u304b\u304b\u304b\u308a\u307e\u305b\u3093\u3067\u3057\u305f\u3002\u30e1\u30fc\u30eb\u30dc\u30c3\u30af\u30b9\u3001\u30ed\u30b0\u3001\u9867\u5ba2\u30c7\u30fc\u30bf\u306f\u3001\u3059\u3079\u3066\u81ea\u793e\u306eNAS\u304b\u3089\u5916\u90e8\u306b\u6301\u3061\u51fa\u3055\u308c\u308b\u3053\u3068\u306f\u3042\u308a\u307e\u305b\u3093\u3067\u3057\u305f\u3002<\/p>\n<\/blockquote>\n\n\n\n<h2 id=\"why-correctly-signed-mail-from-a-nas-still-gets-rejected\" class=\"wp-block-heading\">NAS\u304b\u3089\u9001\u4fe1\u3055\u308c\u305f\u7f72\u540d\u6e08\u307f\u306e\u30e1\u30fc\u30eb\u304c\u62d2\u5426\u3055\u308c\u308b\u7406\u7531<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\u8a8d\u8a3c\u306f\u3042\u306a\u305f\u304c\u8ab0\u3067\u3042\u308b\u304b\u3092\u8a3c\u660e\u3059\u308b\u3082\u306e\u3067\u3042\u308a\u3001\u6b53\u8fce\u3055\u308c\u3066\u3044\u308b\u3053\u3068\u3092\u8a3c\u660e\u3059\u308b\u3082\u306e\u3067\u3082\u3042\u308a\u307e\u305b\u3093\u3002SPF\u3001DKIM\u3001DMARC\u306f\u3001\u30e1\u30c3\u30bb\u30fc\u30b8\u304c\u5b9f\u969b\u306b\u3042\u306a\u305f\u306e\u30c9\u30e1\u30a4\u30f3\u304b\u3089\u9001\u4fe1\u3055\u308c\u305f\u3082\u306e\u3067\u3042\u308b\u3053\u3068\u3092\u53d7\u4fe1\u30b5\u30fc\u30d0\u30fc\u306b\u4f1d\u3048\u3001\u305d\u306e\u5f8c\u3001\u30b5\u30fc\u30d0\u30fc\u306f2\u3064\u76ee\u306e\u8cea\u554f\u3092\u3057\u307e\u3059\u3002\u305d\u308c\u306f\u3001\u30e1\u30c3\u30bb\u30fc\u30b8\u3092\u9001\u4fe1\u3057\u3066\u3044\u308bIP\u30a2\u30c9\u30ec\u30b9\u304b\u3089\u904e\u53bb\u306b\u3069\u306e\u3088\u3046\u306a\u30e1\u30c3\u30bb\u30fc\u30b8\u3092\u53d7\u3051\u53d6\u3063\u305f\u3053\u3068\u304c\u3042\u308b\u304b\u3001\u3068\u3044\u3046\u3053\u3068\u3067\u3059\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u81ea\u793e\u30db\u30b9\u30c8\u578b\u306e\u30e1\u30fc\u30eb\u30b5\u30fc\u30d0\u30fc\u306f\u3001\u901a\u5e38\u30012\u3064\u306e\u65b9\u6cd5\u306e\u3044\u305a\u308c\u304b\u30672\u3064\u76ee\u306e\u7591\u554f\u3092\u89e3\u6d88\u3067\u304d\u307e\u305b\u3093\u3002\u76f4\u63a5\u9001\u4fe1\u3059\u308b\u5834\u5408\u3001\u30d1\u30d6\u30ea\u30c3\u30afIP\u30a2\u30c9\u30ec\u30b9\u306b\u306f\u30a4\u30f3\u30bf\u30fc\u30cd\u30c3\u30c8\u30d7\u30ed\u30d0\u30a4\u30c0\u304b\u3089\u63d0\u4f9b\u3055\u308c\u308b\u6c4e\u7528\u7684\u306a\u9006\u5f15\u304dDNS\u540d\u304c\u4ed8\u4e0e\u3055\u308c\u308b\u3053\u3068\u304c\u591a\u304f\u3001\u591a\u304f\u306e\u53d7\u4fe1\u8005\u306f\u305d\u308c\u3092\u81ea\u5b85\u306e\u63a5\u7d9a\u3068\u3057\u3066\u8a8d\u8b58\u3057\u307e\u3059\u3002\u4e00\u65b9\u3001\u5f53\u793e\u306e\u3088\u3046\u306b\u30d7\u30ed\u30d0\u30a4\u30c0\u72ec\u81ea\u306e\u9001\u4fe1\u30b5\u30fc\u30d0\u30fc\u3092\u7d4c\u7531\u3057\u3066\u9001\u4fe1\u3059\u308b\u5834\u5408\u306f\u3001\u30e1\u30c3\u30bb\u30fc\u30b8\u306f\u6570\u5343\u3082\u306e\u4ed6\u306e\u9867\u5ba2\u3068\u5171\u6709\u3055\u308c\u3066\u3044\u308b\u30de\u30b7\u30f3\u306e\u8a55\u5224\u3092\u5f15\u304d\u7d99\u3050\u3053\u3068\u306b\u306a\u308a\u307e\u3059\u3002<\/p>\n\n\n\n<figure class=\"wp-block-image size-full\"><img decoding=\"async\" width=\"1131\" height=\"344\" sizes=\"(max-width: 1131px) 100vw, 1131px\" src=\"https:\/\/synopower.club\/wp-content\/uploads\/2026\/10\/telenet-bounce-message-considered-spam.webp\" alt=\"SMTP\u30ea\u30ec\u30fc\u5909\u66f4\u524d\u306b\u30d9\u30eb\u30ae\u30fc\u306e\u30e1\u30fc\u30eb\u30dc\u30c3\u30af\u30b9\u30d7\u30ed\u30d0\u30a4\u30c0\u30fc\u304b\u3089\u7f72\u540d\u4ed8\u304d\u6ce8\u6587\u30e1\u30fc\u30eb\u3092\u30b9\u30d1\u30e0\u3068\u3057\u3066\u62d2\u5426\u3059\u308b\u30d0\u30a6\u30f3\u30b9\u30e1\u30c3\u30bb\u30fc\u30b8\u304c\u5c4a\u3044\u305f\u3002\" class=\"wp-image-21895\" srcset=\"https:\/\/synopower.club\/wp-content\/uploads\/2026\/10\/telenet-bounce-message-considered-spam.webp 1131w, https:\/\/synopower.club\/wp-content\/uploads\/2026\/10\/telenet-bounce-message-considered-spam-300x91.webp 300w, https:\/\/synopower.club\/wp-content\/uploads\/2026\/10\/telenet-bounce-message-considered-spam-1024x311.webp 1024w, https:\/\/synopower.club\/wp-content\/uploads\/2026\/10\/telenet-bounce-message-considered-spam-768x234.webp 768w, https:\/\/synopower.club\/wp-content\/uploads\/2026\/10\/telenet-bounce-message-considered-spam-18x5.webp 18w, https:\/\/synopower.club\/wp-content\/uploads\/2026\/10\/telenet-bounce-message-considered-spam-400x122.webp 400w, https:\/\/synopower.club\/wp-content\/uploads\/2026\/10\/telenet-bounce-message-considered-spam-1000x304.webp 1000w\" \/><figcaption class=\"wp-element-caption\">10\u67089\u65e5\u306b\u5f0a\u793e\u306e\u30b5\u30dd\u30fc\u30c8\u30e1\u30fc\u30eb\u30dc\u30c3\u30af\u30b9\u306b\u5c4a\u3044\u305f\u30e1\u30fc\u30eb\u306f\u3001\u9867\u5ba2\u306e\u30a2\u30c9\u30ec\u30b9\u3068\u5f0a\u793e\u306e\u30b5\u30fc\u30d0\u30fc\u30a2\u30c9\u30ec\u30b9\u304c\u4f0f\u305b\u3089\u308c\u305f\u72b6\u614b\u3067\u9001\u4fe1\u3055\u308c\u307e\u3057\u305f\u3002\u62d2\u5426\u306f\u914d\u4fe1\u4e2d\u306b\u30d7\u30ed\u30d0\u30a4\u30c0\u81ea\u8eab\u306e\u30e1\u30fc\u30eb\u30b5\u30fc\u30d0\u30fc\u304b\u3089\u767a\u751f\u3057\u305f\u3082\u306e\u3067\u3059\u3002<\/figcaption><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">\u305d\u308c\u304c\u79c1\u305f\u3061\u306e\u72b6\u6cc1\u3067\u3057\u305f\u3002\u30d0\u30a6\u30f3\u30b9\u30e1\u30fc\u30eb\u306b\u306f\u3001\u30c9\u30e1\u30a4\u30f3\u3084\u7f72\u540d\u306b\u95a2\u3059\u308b\u30a8\u30e9\u30fc\u306f\u542b\u307e\u308c\u3066\u3044\u307e\u305b\u3093\u3067\u3057\u305f\u3002\u3053\u308c\u306f\u7d4c\u8def\u4e0a\u306e\u5224\u65ad\u3067\u3042\u308a\u3001Telenet\u3084GMX\u3068\u3044\u3063\u305f\u30e8\u30fc\u30ed\u30c3\u30d1\u306e\u5927\u624b\u30e1\u30fc\u30eb\u30dc\u30c3\u30af\u30b9\u30d7\u30ed\u30d0\u30a4\u30c0\u30fc\u306f\u3001\u307e\u3055\u306b\u305d\u306e\u30b7\u30b0\u30ca\u30eb\u306b\u5bfe\u3057\u3066\u53b3\u683c\u306a\u30d5\u30a3\u30eb\u30bf\u30ea\u30f3\u30b0\u3092\u884c\u3046\u3053\u3068\u3067\u77e5\u3089\u308c\u3066\u3044\u307e\u3059\u3002\u554f\u984c\u306fNAS\u306e1\u30db\u30c3\u30d7\u5f8c\u306b\u767a\u751f\u3057\u3066\u3044\u305f\u305f\u3081\u3001\u30e1\u30fc\u30eb\u30b5\u30fc\u30d0\u30fc\u5185\u90e8\u3067\u305d\u308c\u3092\u5909\u3048\u308b\u3053\u3068\u306f\u3067\u304d\u307e\u305b\u3093\u3067\u3057\u305f\u3002<\/p>\n\n\n\n<h2 id=\"what-an-smtp-relay-changes-and-what-it-does-not\" class=\"wp-block-heading\">SMTP\u30ea\u30ec\u30fc\u304c\u5909\u66f4\u3059\u308b\u70b9\u3068\u5909\u66f4\u3057\u306a\u3044\u70b9<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">SMTP\u30ea\u30ec\u30fc\u306f\u3001\u6700\u5f8c\u306e\u30db\u30c3\u30d7\u3092\u7f6e\u304d\u63db\u3048\u307e\u3059\u3002\u30b5\u30fc\u30d0\u30fc\u306f\u30dd\u30fc\u30c8587\u3067\u30ea\u30ec\u30fc\u306b\u5bfe\u3057\u3066\u8a8d\u8a3c\u3092\u884c\u3044\u3001\u30e1\u30c3\u30bb\u30fc\u30b8\u3092\u6e21\u3059\u3068\u3001SMTP\u30ea\u30ec\u30fc\u306f\u72ec\u81ea\u306eIP\u30a2\u30c9\u30ec\u30b9\u3068\u9001\u4fe1\u5c65\u6b74\u306b\u57fa\u3065\u3044\u3066\u30e1\u30c3\u30bb\u30fc\u30b8\u3092\u914d\u4fe1\u3057\u307e\u3059\u3002\u30c8\u30e9\u30f3\u30b6\u30af\u30b7\u30e7\u30f3\u30e1\u30fc\u30eb\u30b5\u30fc\u30d3\u30b9\u306f\u307e\u3055\u306b\u3053\u306e\u76ee\u7684\u306e\u305f\u3081\u306b\u5b58\u5728\u3057\u307e\u3059\u3002\u3053\u308c\u3089\u306e\u30b5\u30fc\u30d3\u30b9\u306e\u30a2\u30c9\u30ec\u30b9\u304b\u3089\u306f\u3001\u53d7\u4fe1\u78ba\u8a8d\u3001\u30d1\u30b9\u30ef\u30fc\u30c9\u30ea\u30bb\u30c3\u30c8\u3001\u901a\u77e5\u306e\u307f\u304c\u9001\u4fe1\u3055\u308c\u308b\u305f\u3081\u3001\u53d7\u4fe1\u8005\u306f\u6c4e\u7528\u7684\u306a\u9001\u4fe1\u30b5\u30fc\u30d0\u30fc\u3088\u308a\u3082\u3053\u308c\u3089\u306e\u30b5\u30fc\u30d3\u30b9\u3092\u4fe1\u983c\u3057\u307e\u3059\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u512a\u308c\u305fSMTP\u30ea\u30ec\u30fc\u306f\u3001\u30c9\u30e1\u30a4\u30f3\u306eDKIM\u30ad\u30fc\u3067\u30e1\u30c3\u30bb\u30fc\u30b8\u306b\u7f72\u540d\u3059\u308b\u305f\u3081\u3001\u9867\u5ba2\u306f\u5f15\u304d\u7d9a\u304d\u3042\u306a\u305f\u306e\u30a2\u30c9\u30ec\u30b9\u3092\u78ba\u8a8d\u3067\u304d\u3001DMARC\u3082\u6b63\u5e38\u306b\u901a\u904e\u3057\u307e\u3059\u3002\u305f\u3060\u3057\u3001\u4e0d\u6b63\u306a\u30b3\u30f3\u30c6\u30f3\u30c4\u3001\u6b20\u843d\u3057\u3066\u3044\u308bSPF\u30ec\u30b3\u30fc\u30c9\u3001\u307e\u305f\u306f\u30e1\u30fc\u30eb\u3092\u8981\u6c42\u3057\u3066\u3044\u306a\u3044\u4eba\u306e\u30ea\u30b9\u30c8\u3092\u4fee\u5fa9\u3059\u308b\u3053\u3068\u306f\u3067\u304d\u307e\u305b\u3093\u3002\u307e\u305a\u306f\u8a8d\u8a3c\u3092\u4fee\u6b63\u3057\u3001\u6b21\u306b\u7d4c\u8def\u3092\u78ba\u8a8d\u3057\u3066\u304f\u3060\u3055\u3044\u3002<\/p>\n\n\n\n<h2 id=\"why-we-chose-resend-as-the-smtp-relay\" class=\"wp-block-heading\">SMTP\u30ea\u30ec\u30fc\u3068\u3057\u3066Resend\u3092\u9078\u3093\u3060\u7406\u7531<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\u6700\u521d\u306b\u8a66\u307f\u305f\u306e\u306fAmazon SES\u3067\u3057\u305f\u3002\u30c9\u30e1\u30a4\u30f3\u3092\u78ba\u8a8d\u3057\u30011\u65e5\u3042\u305f\u308a20\uff5e50\u901a\u306e\u30c8\u30e9\u30f3\u30b6\u30af\u30b7\u30e7\u30f3\u30e1\u30fc\u30eb\u3092\u9001\u4fe1\u3059\u308b\u4e88\u5b9a\u3067\u3042\u308b\u3053\u3068\u3092\u4f1d\u3048\u307e\u3057\u305f\u304c\u3001\u7fcc\u65e5\u3001\u7406\u7531\u3082\u544a\u3052\u3089\u308c\u305a\u306b\u672c\u756a\u74b0\u5883\u3078\u306e\u30a2\u30af\u30bb\u30b9\u3092\u62d2\u5426\u3055\u308c\u307e\u3057\u305f\u3002\u3053\u308c\u306f\u65b0\u898f\u30a2\u30ab\u30a6\u30f3\u30c8\u3067\u306f\u3088\u304f\u3042\u308b\u3053\u3068\u3067\u3001\u30e9\u30a4\u30bb\u30f3\u30b9\u30ad\u30fc\u304c\u5c4a\u304f\u306e\u3092\u5f85\u3063\u3066\u3044\u308b\u72b6\u614b\u306b\u306a\u3063\u3066\u3057\u307e\u3044\u307e\u3057\u305f\u3002<\/p>\n\n\n\n<figure class=\"wp-block-image size-full\"><img decoding=\"async\" width=\"960\" height=\"196\" sizes=\"(max-width: 960px) 100vw, 960px\" src=\"https:\/\/synopower.club\/wp-content\/uploads\/2026\/10\/amazon-ses-production-access-declined.webp\" alt=\"Amazon SES\u304b\u3089\u3001\u65b0\u898f\u30a2\u30ab\u30a6\u30f3\u30c8\u306e\u904b\u7528\u74b0\u5883\u3078\u306e\u30a2\u30af\u30bb\u30b9\u3092\u62d2\u5426\u3059\u308b\u30e1\u30fc\u30eb\u304c\u5c4a\u3044\u305f\u304c\u3001\u7406\u7531\u306f\u793a\u3055\u308c\u306a\u304b\u3063\u305f\u3002\" class=\"wp-image-21896\" srcset=\"https:\/\/synopower.club\/wp-content\/uploads\/2026\/10\/amazon-ses-production-access-declined.webp 960w, https:\/\/synopower.club\/wp-content\/uploads\/2026\/10\/amazon-ses-production-access-declined-300x61.webp 300w, https:\/\/synopower.club\/wp-content\/uploads\/2026\/10\/amazon-ses-production-access-declined-768x157.webp 768w, https:\/\/synopower.club\/wp-content\/uploads\/2026\/10\/amazon-ses-production-access-declined-18x4.webp 18w, https:\/\/synopower.club\/wp-content\/uploads\/2026\/10\/amazon-ses-production-access-declined-400x82.webp 400w\" \/><figcaption class=\"wp-element-caption\">Amazon Web Services\u304b\u3089\u306e\u8fd4\u4fe1\u306e\u5192\u982d\u90e8\u5206\u3067\u3059\u3002\u30e1\u30c3\u30bb\u30fc\u30b8\u306e\u6b8b\u308a\u306e\u90e8\u5206\u3067\u306f\u3001\u30ec\u30d3\u30e5\u30fc\u3067\u306f\u5171\u6709\u3067\u304d\u306a\u3044\u8981\u7d20\u3082\u8003\u616e\u3055\u308c\u3066\u3044\u308b\u305f\u3081\u3001\u4fee\u6b63\u3059\u3079\u304d\u5177\u4f53\u7684\u306a\u554f\u984c\u306f\u306a\u304b\u3063\u305f\u3068\u8aac\u660e\u3055\u308c\u3066\u3044\u307e\u3059\u3002<\/figcaption><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">\u518d\u9001\u4fe1\u306f2\u56de\u76ee\u306e\u8a66\u307f\u3067\u3001\u767b\u9332\u5f8c\u7d0410\u5206\u3067\u5f53\u793e\u306e\u30c9\u30e1\u30a4\u30f3\u5b9b\u3066\u306e\u7f72\u540d\u4ed8\u304d\u30e1\u30fc\u30eb\u3092\u9001\u4fe1\u3067\u304d\u308b\u3088\u3046\u306b\u306a\u308a\u307e\u3057\u305f\u3002Synology\u3067\u30db\u30b9\u30c6\u30a3\u30f3\u30b0\u3055\u308c\u3066\u3044\u308b\u5c0f\u898f\u6a21\u30b7\u30e7\u30c3\u30d7\u306b\u3068\u3063\u3066\u3001\u3053\u306e\u30b5\u30fc\u30d3\u30b9\u304c\u9069\u3057\u3066\u3044\u305f\u7406\u7531\u306f3\u3064\u3042\u308a\u307e\u3059\u3002<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>\u3053\u308c\u306f\u6a19\u6e96\u7684\u306aSMTP\u901a\u4fe1\u3067\u3059\u3002<\/strong> \u30d7\u30e9\u30b0\u30a4\u30f3\u3084API\u306e\u7d71\u5408\u306f\u4e0d\u8981\u306a\u306e\u3067\u3001NAS\u4e0a\u306e\u30e1\u30fc\u30eb\u30b5\u30fc\u30d0\u30fc\u306f\u8ffd\u52a0\u30bd\u30d5\u30c8\u30a6\u30a7\u30a2\u306a\u3057\u3067SMTP\u30ea\u30ec\u30fc\u3068\u3057\u3066\u4f7f\u7528\u3067\u304d\u307e\u3059\u3002<\/li>\n\n\n\n<li><strong>\u7121\u6599\u30d7\u30e9\u30f3\u306f\u5c0f\u898f\u6a21\u5e97\u8217\u3092\u5bfe\u8c61\u3068\u3057\u3066\u3044\u307e\u3059\u3002<\/strong> 2026\u5e7410\u6708\u6642\u70b9\u3067\u306f\u3001\u6708\u95933,000\u901a\u30011\u65e5100\u901a\u306e\u30e1\u30fc\u30eb\u9001\u4fe1\u30683\u3064\u306e\u30c9\u30e1\u30a4\u30f3\u306e\u4f7f\u7528\u304c\u8a31\u53ef\u3055\u308c\u307e\u3059\u304c\u3001\u3053\u308c\u306f\u5f53\u793e\u306e\u6ce8\u6587\u91cf\u3092\u306f\u308b\u304b\u306b\u4e0a\u56de\u3063\u3066\u3044\u307e\u3059\u3002<\/li>\n\n\n\n<li><strong>Cloudflare\u3067\u306f\u30c9\u30e1\u30a4\u30f3\u8a8d\u8a3c\u306f\u81ea\u52d5\u7684\u306b\u884c\u308f\u308c\u307e\u3059\u3002<\/strong> 1\u3064\u306e\u8a8d\u8a3c\u753b\u9762\u3067\u3001\u5fc5\u8981\u306aDNS\u30ec\u30b3\u30fc\u30c9\u304c\u3059\u3079\u3066\u4f5c\u6210\u3055\u308c\u307e\u3057\u305f\u3002<\/li>\n\n\n\n<li><strong>\u3059\u3079\u3066\u306e\u30e1\u30c3\u30bb\u30fc\u30b8\u306f\u30c0\u30c3\u30b7\u30e5\u30dc\u30fc\u30c9\u306b\u8868\u793a\u3055\u308c\u307e\u3059\u3002<\/strong> \u53d7\u4fe1\u30b5\u30fc\u30d0\u30fc\u304c\u5404\u30e1\u30fc\u30eb\u3092\u53d7\u3051\u5165\u308c\u305f\u304b\u3001\u62d2\u5426\u3057\u305f\u304b\u3092\u78ba\u8a8d\u3067\u304d\u307e\u3059\u3002<\/li>\n<\/ul>\n\n\n\n<figure class=\"wp-block-image size-full\"><img decoding=\"async\" width=\"1274\" height=\"995\" sizes=\"(max-width: 1274px) 100vw, 1274px\" src=\"https:\/\/synopower.club\/wp-content\/uploads\/2026\/10\/resend-pricing-free-plan.webp\" alt=\"SMTP\u30ea\u30ec\u30fc\u7528\u306e\u6708\u95933,000\u901a\u306e\u30e1\u30fc\u30eb\u9001\u4fe1\u304c\u53ef\u80fd\u306a\u7121\u6599\u30d7\u30e9\u30f3\u3092\u8868\u793a\u3059\u308b\u6599\u91d1\u30da\u30fc\u30b8\u3092\u518d\u9001\u3057\u307e\u3059\" class=\"wp-image-21890\" srcset=\"https:\/\/synopower.club\/wp-content\/uploads\/2026\/10\/resend-pricing-free-plan.webp 1274w, https:\/\/synopower.club\/wp-content\/uploads\/2026\/10\/resend-pricing-free-plan-300x234.webp 300w, https:\/\/synopower.club\/wp-content\/uploads\/2026\/10\/resend-pricing-free-plan-1024x800.webp 1024w, https:\/\/synopower.club\/wp-content\/uploads\/2026\/10\/resend-pricing-free-plan-768x600.webp 768w, https:\/\/synopower.club\/wp-content\/uploads\/2026\/10\/resend-pricing-free-plan-15x12.webp 15w, https:\/\/synopower.club\/wp-content\/uploads\/2026\/10\/resend-pricing-free-plan-400x312.webp 400w, https:\/\/synopower.club\/wp-content\/uploads\/2026\/10\/resend-pricing-free-plan-1000x781.webp 1000w\" \/><figcaption class=\"wp-element-caption\">2026\u5e7410\u6708\u6642\u70b9\u306e\u518d\u9001\u4fe1\u6599\u91d1\u30d7\u30e9\u30f3\u3002\u53d7\u4fe1\u30c9\u30e1\u30a4\u30f3\u304c\u3054\u304f\u5c11\u6570\u3067\u3042\u308c\u3070\u3001\u7121\u6599\u30d7\u30e9\u30f3\u3067\u5341\u5206\u3067\u3059\u3002<\/figcaption><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">\u3042\u308b\u4e00\u70b9\u306b\u601d\u308f\u305a\u7b11\u307f\u304c\u3053\u307c\u308c\u305f\u3002\u6700\u521d\u306e\u30c6\u30b9\u30c8\u3067\u9001\u4fe1\u3057\u305f\u30e1\u30c3\u30bb\u30fc\u30b8\u306e\u30d8\u30c3\u30c0\u30fc\u306b\u306f\u3001\u6771\u4eac\u306b\u3042\u308bAmazon SES\u306e\u30a4\u30f3\u30d5\u30e9\u30b9\u30c8\u30e9\u30af\u30c1\u30e3\u3092\u7d4c\u7531\u3057\u3066\u9001\u4fe1\u3055\u308c\u305f\u3053\u3068\u304c\u793a\u3055\u308c\u3066\u3044\u305f\u306e\u3060\u3002Resend\u306f\u3001\u9001\u4fe1\u8005\u306e\u8a55\u5224\u3084\u627f\u8a8d\u3068\u3044\u3063\u305f\u8981\u7d20\u304c\u65e2\u306b\u8003\u616e\u3055\u308c\u305f\u4e0a\u3067\u3001\u304b\u3064\u3066\u79c1\u305f\u3061\u306e\u7533\u8acb\u3092\u5374\u4e0b\u3057\u305f\u307e\u3055\u306b\u305d\u306e\u30d7\u30e9\u30c3\u30c8\u30d5\u30a9\u30fc\u30e0\u4e0a\u306b\u69cb\u7bc9\u3055\u308c\u3066\u3044\u308b\u3002<\/p>\n\n\n\n<h2 id=\"relay-everything-or-only-the-domains-that-reject-you\" class=\"wp-block-heading\">\u3059\u3079\u3066\u3092\u4e2d\u7d99\u3059\u308b\u3079\u304d\u304b\u3001\u305d\u308c\u3068\u3082\u62d2\u5426\u3059\u308b\u30c9\u30e1\u30a4\u30f3\u3060\u3051\u3092\u4e2d\u7d99\u3059\u308b\u3079\u304d\u304b\uff1f<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\u307b\u3068\u3093\u3069\u306e\u30ac\u30a4\u30c9\u3067\u306f\u3001\u3059\u3079\u3066\u306e\u9001\u4fe1\u30e1\u30fc\u30eb\u3092\u65b0\u3057\u3044SMTP\u30ea\u30ec\u30fc\u7d4c\u7531\u3067\u9001\u4fe1\u3059\u308b\u3088\u3046\u306b\u6307\u793a\u3057\u3066\u3044\u307e\u3059\u304c\u3001\u79c1\u305f\u3061\u306f\u305d\u3046\u3057\u307e\u305b\u3093\u3067\u3057\u305f\u3002\u305d\u306e\u7406\u7531\u306fSynology MailPlus\u306e\u304a\u304b\u3052\u3067\u3059\u3002Synology MailPlus\u306eSMTP\u30ea\u30ec\u30fc\u8a2d\u5b9a\u3067\u306f\u4f8b\u5916\u30eb\u30fc\u30eb\u304c\u8a2d\u5b9a\u3067\u304d\u3001\u5404\u30eb\u30fc\u30eb\u306b\u306f\u72ec\u81ea\u306e\u30b5\u30fc\u30d0\u30fc\u3001\u30dd\u30fc\u30c8\u3001\u8a8d\u8a3c\u60c5\u5831\u304c\u542b\u307e\u308c\u3066\u3044\u307e\u3059\u3002\u30eb\u30fc\u30eb\u306b\u30ea\u30b9\u30c8\u3055\u308c\u3066\u3044\u308b\u30c9\u30e1\u30a4\u30f3\u5b9b\u3066\u306e\u30e1\u30fc\u30eb\u306f\u305d\u306e\u30eb\u30fc\u30eb\u306b\u5f93\u3063\u3066\u9001\u4fe1\u3055\u308c\u3001\u305d\u308c\u4ee5\u5916\u306e\u30e1\u30fc\u30eb\u306f\u30c7\u30d5\u30a9\u30eb\u30c8\u30eb\u30fc\u30c8\u3092\u4f7f\u7528\u3057\u307e\u3059\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u3053\u306e\u3088\u3046\u306b\u30c8\u30e9\u30d5\u30a3\u30c3\u30af\u3092\u5206\u5272\u3059\u308b\u3053\u3068\u306f\u3001\u30d3\u30b8\u30cd\u30b9\u30e1\u30fc\u30eb\u30b5\u30fc\u30d0\u30fc\u306b\u3068\u3063\u3066\u5927\u304d\u306a\u30e1\u30ea\u30c3\u30c8\u304c\u3042\u308a\u307e\u3059\u3002<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>\u901a\u5e38\u306e\u901a\u4fe1\u306f\u305d\u306e\u307e\u307e\u7dad\u6301\u3055\u308c\u308b\u3002<\/strong> \u8fd4\u4fe1\u3001\u30b9\u30ec\u30c3\u30c9\u3001\u304a\u3088\u3073\u8907\u6570\u306e\u53d7\u4fe1\u8005\u3092\u542b\u3080\u30e1\u30c3\u30bb\u30fc\u30b8\u306f\u3001\u5143\u306e\u30d8\u30c3\u30c0\u30fc\u3092\u4fdd\u6301\u3057\u307e\u3059\u3002<\/li>\n\n\n\n<li><strong>\u7b2c\u4e09\u8005\u3092\u7d4c\u7531\u3059\u308b\u90f5\u4fbf\u7269\u306e\u91cf\u304c\u6e1b\u308a\u307e\u3059\u3002<\/strong> 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SMTP\u30ea\u30ec\u30fc\u3092\u518d\u9001\u4fe1\u6a5f\u80fd\u4ed8\u304d\u3067\u8a2d\u5b9a\u3059\u308b4\u3064\u306e\u30b9\u30c6\u30c3\u30d7<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">SMTP\u30ea\u30ec\u30fc\u306e\u8a2d\u5b9a\u306f\u3059\u3079\u3066\u3001\u30d6\u30e9\u30a6\u30b6\u306e2\u3064\u306e\u30bf\u30d6\uff08DSM\u5185\u306eResend\u30c0\u30c3\u30b7\u30e5\u30dc\u30fc\u30c9\u3068MailPlus\u30b5\u30fc\u30d0\u30fc\u30b3\u30f3\u30bd\u30fc\u30eb\uff09\u3067\u884c\u3044\u307e\u3059\u3002\u672c\u756a\u30b7\u30b9\u30c6\u30e0\u306e\u5834\u5408\u306f\u3001\u307e\u305a\u30e1\u30fc\u30eb\u30b5\u30fc\u30d0\u30fc\u306e\u8a2d\u5b9a\u3092\u30b9\u30ca\u30c3\u30d7\u30b7\u30e7\u30c3\u30c8\u3059\u308b\u304b\u30a8\u30af\u30b9\u30dd\u30fc\u30c8\u3057\u3066\u304f\u3060\u3055\u3044\u3002<\/p>\n\n\n<div id=\"rank-math-howto\" class=\"rank-math-block\" >\n<div class=\"rank-math-howto-description\">\n\n<\/div>\n\n<div class=\"rank-math-steps\">\n<div id=\"step-1\" class=\"rank-math-step\">\n<h3 class=\"rank-math-step-title\">\u30c9\u30e1\u30a4\u30f3\u3092Resend\u306b\u8ffd\u52a0\u3057\u3001DNS\u30ec\u30b3\u30fc\u30c9\u3092\u516c\u958b\u3057\u307e\u3059\u3002<\/h3>\n<div class=\"rank-math-step-content\"><p>Resend\u30a2\u30ab\u30a6\u30f3\u30c8\u3092\u4f5c\u6210\u3057\u3001\u300c\u30c9\u30e1\u30a4\u30f3\u300d\u3092\u958b\u3044\u3066\u9001\u4fe1\u5143\u306e\u30c9\u30e1\u30a4\u30f3\u3092\u8ffd\u52a0\u3057\u307e\u3059\u3002\u3053\u306e\u30b9\u30c6\u30c3\u30d7\u3067\u30ea\u30fc\u30b8\u30e7\u30f3\u3092\u9078\u629e\u3057\u3066\u304f\u3060\u3055\u3044\u3002\u3059\u308b\u3068\u3001Resend\u306fDKIM\u30ec\u30b3\u30fc\u30c9\u3068\u30d0\u30a6\u30f3\u30b9\u30b5\u30d6\u30c9\u30e1\u30a4\u30f3\u7528\u306e\u30ec\u30b3\u30fc\u30c9\u30922\u3064\u8868\u793a\u3057\u307e\u3059\u3002Cloudflare DNS\u3092\u4f7f\u7528\u3057\u3066\u3044\u308b\u5834\u5408\u306f\u3001\u300c\u81ea\u52d5\u8a2d\u5b9a\u300d\u30dc\u30bf\u30f3\u3092\u30af\u30ea\u30c3\u30af\u3059\u308b\u3068\u3001\u8a8d\u8a3c\u753b\u9762\u304c1\u56de\u8868\u793a\u3055\u308c\u305f\u5f8c\u306b\u30ec\u30b3\u30fc\u30c9\u304c\u4f5c\u6210\u3055\u308c\u307e\u3059\u3002\u305d\u306e\u4ed6\u306eDNS\u30db\u30b9\u30c8\u3092\u4f7f\u7528\u3057\u3066\u3044\u308b\u5834\u5408\u306f\u3001\u30ec\u30b3\u30fc\u30c9\u3092\u624b\u52d5\u3067\u30b3\u30d4\u30fc\u3057\u3066\u304f\u3060\u3055\u3044\u3002\u65e2\u5b58\u306eSPF\u3001DKIM\u3001DMARC\u30ec\u30b3\u30fc\u30c9\u306f\u305d\u306e\u307e\u307e\u306b\u3057\u3066\u304a\u3044\u3066\u304f\u3060\u3055\u3044\u3002<\/p>\n<\/div>\n<\/div>\n<div id=\"step-2\" class=\"rank-math-step\">\n<h3 class=\"rank-math-step-title\">\u691c\u8a3c\u304c\u5b8c\u4e86\u3059\u308b\u307e\u3067\u5f85\u3061\u3001\u305d\u306e\u5f8c\u9001\u4fe1\u5c02\u7528\u306eAPI\u30ad\u30fc\u3092\u4f5c\u6210\u3057\u307e\u3059\u3002<\/h3>\n<div class=\"rank-math-step-content\"><p>\u691c\u8a3c\u306b\u306f\u6570\u5206\u304b\u304b\u308a\u307e\u3057\u305f\u3002\u30c9\u30e1\u30a4\u30f3\u306e\u72b6\u614b\u304c\u300c\u691c\u8a3c\u6e08\u307f\u300d\u3068\u8868\u793a\u3055\u308c\u305f\u3089\u3001API\u30ad\u30fc\u3092\u958b\u304d\u3001\u9001\u4fe1\u30a2\u30af\u30bb\u30b9\u6a29\u9650\u3092\u6301\u3064\u30ad\u30fc\u3092\u4f5c\u6210\u3057\u307e\u3059\u3002\u5fc5\u8981\u306b\u5fdc\u3058\u3066\u3001\u305d\u306e\u30c9\u30e1\u30a4\u30f3\u306e\u307f\u306b\u30a2\u30af\u30bb\u30b9\u6a29\u9650\u3092\u4ed8\u4e0e\u3057\u3066\u304f\u3060\u3055\u3044\u3002\u30ad\u30fc\u5168\u4f53\u306f\u4e00\u5ea6\u3057\u304b\u8868\u793a\u3055\u308c\u306a\u3044\u305f\u3081\u3001\u3059\u3050\u306b\u30b3\u30d4\u30fc\u3057\u3066\u304f\u3060\u3055\u3044\u3002\u3053\u306e\u30ad\u30fc\u306fSMTP\u30ea\u30ec\u30fc\u306e\u30d1\u30b9\u30ef\u30fc\u30c9\u306b\u306a\u308a\u307e\u3059\u3002<\/p>\n<\/div>\n<\/div>\n<div id=\"step-3\" class=\"rank-math-step\">\n<h3 class=\"rank-math-step-title\">MailPlus\u30b5\u30fc\u30d0\u30fc\u3067\u53d7\u4fe1\u8005\u30eb\u30fc\u30eb\u3092\u4f5c\u6210\u3059\u308b<\/h3>\n<div class=\"rank-math-step-content\"><p>MailPlus\u30b5\u30fc\u30d0\u30fc\u3067\u3001\u300c\u30e1\u30fc\u30eb\u914d\u4fe1\u300d\u3092\u958b\u304d\u3001\u300c\u30ea\u30ec\u30fc\u8a2d\u5b9a\u300d\u2192\u300c\u4f8b\u5916\u30eb\u30fc\u30eb\u300d\u306e\u9806\u306b\u9078\u629e\u3057\u3001\u300c\u53d7\u4fe1\u8005\u30eb\u30fc\u30eb\u300d\u30bf\u30d6\u3067\u30eb\u30fc\u30eb\u3092\u4f5c\u6210\u3057\u307e\u3059\u3002\u30b5\u30fc\u30d0\u30fc\u306b\u300csmtp.resend.com\u300d\u3001\u30dd\u30fc\u30c8\u306b\u300c587\u300d\u3068\u5165\u529b\u3057\u3001\u300c\u30bb\u30ad\u30e5\u30a2\u63a5\u7d9a\u300d\u3068\u300c\u8a8d\u8a3c\u300d\u306e\u30c1\u30a7\u30c3\u30af\u30dc\u30c3\u30af\u30b9\u3092\u30aa\u30f3\u306b\u3057\u307e\u3059\u3002\u30a2\u30ab\u30a6\u30f3\u30c8\u306b\u300cresend\u300d\u3068\u5165\u529b\u3057\u3001\u30d1\u30b9\u30ef\u30fc\u30c9\u306bAPI\u30ad\u30fc\u3092\u8cbc\u308a\u4ed8\u3051\u307e\u3059\u3002\u5404\u53d7\u4fe1\u8005\u30c9\u30e1\u30a4\u30f3\u3092\u30ea\u30b9\u30c8\u306b\u8ffd\u52a0\u3057\u3001\u78ba\u8a8d\u3057\u3066\u9069\u7528\u3057\u307e\u3059\u3002<\/p>\n<\/div>\n<\/div>\n<div id=\"step-4\" class=\"rank-math-step\">\n<h3 class=\"rank-math-step-title\">\u30c6\u30b9\u30c8\u3092\u9001\u4fe1\u3057\u3001\u4e21\u9762\u304b\u3089\u7d50\u679c\u3092\u8aad\u307f\u53d6\u3063\u3066\u304f\u3060\u3055\u3044\u3002<\/h3>\n<div class=\"rank-math-step-content\"><p>\u30ea\u30b9\u30c8\u3055\u308c\u3066\u3044\u308b\u30c9\u30e1\u30a4\u30f3\u306e\u3044\u305a\u308c\u304b\u306e\u30e1\u30fc\u30eb\u30dc\u30c3\u30af\u30b9\u306b\u30e1\u30c3\u30bb\u30fc\u30b8\u3092\u9001\u4fe1\u3057\u3066\u304f\u3060\u3055\u3044\u3002MailPlus Server \u3067\u306f\u3001\u6570\u79d2\u5f8c\u306b\u30ad\u30e5\u30fc\u30da\u30fc\u30b8\u304c\u7a7a\u306b\u306a\u3063\u3066\u3044\u308b\u306f\u305a\u3067\u3059\u3002\u518d\u9001\u4fe1\u753b\u9762\u306e\u30e1\u30fc\u30eb\u30da\u30fc\u30b8\u3067\u306f\u3001\u30e1\u30c3\u30bb\u30fc\u30b8\u304c\u914d\u4fe1\u6e08\u307f\u3068\u3057\u3066\u8868\u793a\u3055\u308c\u308b\u306f\u305a\u3067\u3059\u3002\u6700\u5f8c\u306b\u3001\u53d7\u4fe1\u5074\u3067\u30e1\u30c3\u30bb\u30fc\u30b8\u3092\u958b\u304d\u3001SPF\u3001DKIM\u3001DMARC \u306e\u3059\u3079\u3066\u304c\u81ea\u5206\u306e\u30c9\u30e1\u30a4\u30f3\u306b\u5bfe\u3057\u3066\u5408\u683c\u3057\u3066\u3044\u308b\u3053\u3068\u3092\u78ba\u8a8d\u3057\u3066\u304f\u3060\u3055\u3044\u3002<\/p>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n\n\n\n\n\n\n<figure class=\"wp-block-image size-full\"><img decoding=\"async\" width=\"1218\" height=\"1230\" sizes=\"(max-width: 1218px) 100vw, 1218px\" src=\"https:\/\/synopower.club\/wp-content\/uploads\/2026\/10\/resend-domain-dns-records-cloudflare.webp\" alt=\"Cloudflare\u3067\u4f5c\u6210\u3055\u308c\u305fDKIM\u304a\u3088\u3073SPF DNS\u30ec\u30b3\u30fc\u30c9\u3092\u4e00\u89a7\u8868\u793a\u3059\u308b\u30c9\u30e1\u30a4\u30f3\u30da\u30fc\u30b8\u3092\u518d\u9001\u4fe1\u3057\u307e\u3059\u3002\" class=\"wp-image-21888\" srcset=\"https:\/\/synopower.club\/wp-content\/uploads\/2026\/10\/resend-domain-dns-records-cloudflare.webp 1218w, https:\/\/synopower.club\/wp-content\/uploads\/2026\/10\/resend-domain-dns-records-cloudflare-297x300.webp 297w, https:\/\/synopower.club\/wp-content\/uploads\/2026\/10\/resend-domain-dns-records-cloudflare-1014x1024.webp 1014w, https:\/\/synopower.club\/wp-content\/uploads\/2026\/10\/resend-domain-dns-records-cloudflare-150x150.webp 150w, https:\/\/synopower.club\/wp-content\/uploads\/2026\/10\/resend-domain-dns-records-cloudflare-768x776.webp 768w, https:\/\/synopower.club\/wp-content\/uploads\/2026\/10\/resend-domain-dns-records-cloudflare-12x12.webp 12w, https:\/\/synopower.club\/wp-content\/uploads\/2026\/10\/resend-domain-dns-records-cloudflare-400x404.webp 400w, https:\/\/synopower.club\/wp-content\/uploads\/2026\/10\/resend-domain-dns-records-cloudflare-1000x1010.webp 1000w, https:\/\/synopower.club\/wp-content\/uploads\/2026\/10\/resend-domain-dns-records-cloudflare-100x100.webp 100w\" \/><figcaption class=\"wp-element-caption\">\u30b9\u30c6\u30c3\u30d71\uff1aCloudflare\u304c\u4f5c\u6210\u3057\u305f\u6570\u5206\u5f8c\u306b\u3001Resend\u304c\u8981\u6c42\u3057\u305f\u30ec\u30b3\u30fc\u30c9\uff08DKIM\u30ad\u30fc\u30682\u3064\u306eCNAME\u30ec\u30b3\u30fc\u30c9\uff09\u304c\u9001\u4fe1\u3055\u308c\u307e\u3057\u305f\u3002\u305d\u306e\u5f8c\u3059\u3050\u306b\u30b9\u30c6\u30fc\u30bf\u30b9\u304c\u300c\u691c\u8a3c\u6e08\u307f\u300d\u306b\u5909\u66f4\u3055\u308c\u307e\u3057\u305f\u3002<\/figcaption><\/figure>\n\n\n\n<figure class=\"wp-block-image size-full\"><img decoding=\"async\" width=\"1165\" height=\"275\" sizes=\"(max-width: 1165px) 100vw, 1165px\" src=\"https:\/\/synopower.club\/wp-content\/uploads\/2026\/10\/resend-api-key-sending-access.webp\" alt=\"SMTP\u30ea\u30ec\u30fc\u30d1\u30b9\u30ef\u30fc\u30c9\u3068\u3057\u3066\u4f7f\u7528\u3055\u308c\u308b\u3001\u9001\u4fe1\u30a2\u30af\u30bb\u30b9\u6a29\u9650\u4ed8\u304d\u306eAPI\u30ad\u30fc\u3092\u518d\u9001\u4fe1\u3057\u307e\u3059\u3002\" class=\"wp-image-21889\" srcset=\"https:\/\/synopower.club\/wp-content\/uploads\/2026\/10\/resend-api-key-sending-access.webp 1165w, https:\/\/synopower.club\/wp-content\/uploads\/2026\/10\/resend-api-key-sending-access-300x71.webp 300w, https:\/\/synopower.club\/wp-content\/uploads\/2026\/10\/resend-api-key-sending-access-1024x242.webp 1024w, https:\/\/synopower.club\/wp-content\/uploads\/2026\/10\/resend-api-key-sending-access-768x181.webp 768w, https:\/\/synopower.club\/wp-content\/uploads\/2026\/10\/resend-api-key-sending-access-18x4.webp 18w, https:\/\/synopower.club\/wp-content\/uploads\/2026\/10\/resend-api-key-sending-access-400x94.webp 400w, https:\/\/synopower.club\/wp-content\/uploads\/2026\/10\/resend-api-key-sending-access-1000x236.webp 1000w\" \/><figcaption class=\"wp-element-caption\">\u30b9\u30c6\u30c3\u30d72\uff1a\u9001\u4fe1\u5c02\u7528\u306e\u30ad\u30fc\u3002\u30c8\u30fc\u30af\u30f3\u306f\u3053\u3053\u3067\u306f\u975e\u8868\u793a\u306b\u306a\u3063\u3066\u304a\u308a\u3001\u300c\u6700\u5f8c\u306b\u4f7f\u7528\u3057\u305f\u65e5\u6642\u300d\u5217\u306f\u5f8c\u3067\u78ba\u8a8d\u3059\u308b\u306e\u306b\u4fbf\u5229\u3067\u3059\u3002<\/figcaption><\/figure>\n\n\n\n<figure class=\"wp-block-image size-full\"><img decoding=\"async\" width=\"1421\" height=\"1088\" sizes=\"(max-width: 1421px) 100vw, 1421px\" src=\"https:\/\/synopower.club\/wp-content\/uploads\/2026\/10\/mailplus-smtp-relay-recipient-rule-resend.webp\" alt=\"Synology MailPlus\u30b5\u30fc\u30d0\u30fc\u4f8b\u5916\u30eb\u30fc\u30eb\u306b\u3088\u308a\u30012\u3064\u306e\u53d7\u4fe1\u8005\u30c9\u30e1\u30a4\u30f3\u304c\u518d\u9001\u4fe1SMTP\u30ea\u30ec\u30fc\u7d4c\u7531\u3067\u9001\u4fe1\u3055\u308c\u307e\u3059\u3002\" class=\"wp-image-21887\" srcset=\"https:\/\/synopower.club\/wp-content\/uploads\/2026\/10\/mailplus-smtp-relay-recipient-rule-resend.webp 1421w, https:\/\/synopower.club\/wp-content\/uploads\/2026\/10\/mailplus-smtp-relay-recipient-rule-resend-300x230.webp 300w, https:\/\/synopower.club\/wp-content\/uploads\/2026\/10\/mailplus-smtp-relay-recipient-rule-resend-1024x784.webp 1024w, https:\/\/synopower.club\/wp-content\/uploads\/2026\/10\/mailplus-smtp-relay-recipient-rule-resend-768x588.webp 768w, https:\/\/synopower.club\/wp-content\/uploads\/2026\/10\/mailplus-smtp-relay-recipient-rule-resend-16x12.webp 16w, https:\/\/synopower.club\/wp-content\/uploads\/2026\/10\/mailplus-smtp-relay-recipient-rule-resend-400x306.webp 400w, https:\/\/synopower.club\/wp-content\/uploads\/2026\/10\/mailplus-smtp-relay-recipient-rule-resend-1000x766.webp 1000w\" \/><figcaption class=\"wp-element-caption\">\u30b9\u30c6\u30c3\u30d73\uff1aMailPlus\u30b5\u30fc\u30d0\u30fc\u306e\u53d7\u4fe1\u8005\u30eb\u30fc\u30eb\u3002\u30d7\u30ed\u30d0\u30a4\u30c0\u30fc\u30b5\u30fc\u30d0\u30fc\u7528\u306e\u53e4\u3044\u30eb\u30fc\u30eb\u304c\u305d\u306e\u4e0a\u306b\u3042\u308a\u3001\u7121\u52b9\u306b\u306a\u3063\u3066\u3044\u307e\u3059\u3002\u3053\u306e\u30b9\u30af\u30ea\u30fc\u30f3\u30b7\u30e7\u30c3\u30c8\u3067\u306f\u3001\u30d1\u30b9\u30ef\u30fc\u30c9\u30d5\u30a3\u30fc\u30eb\u30c9\u306f\u7a7a\u767d\u306b\u306a\u3063\u3066\u3044\u307e\u3059\u3002<\/figcaption><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">DNS\u5074\u306b\u3064\u3044\u3066\u306f\u3001\u3082\u30461\u6587\u88dc\u8db3\u3057\u3066\u304a\u304d\u307e\u3059\u3002Resend\u306f\u72ec\u81ea\u306eDKIM\u30bb\u30ec\u30af\u30bf\u3067\u7f72\u540d\u3057\u3001\u30d0\u30a6\u30f3\u30b9\u30e1\u30fc\u30eb\u306b\u306f\u72ec\u81ea\u306e\u30b5\u30d6\u30c9\u30e1\u30a4\u30f3\u3092\u4f7f\u7528\u3059\u308b\u305f\u3081\u3001\u8ffd\u52a0\u3059\u308b\u30ec\u30b3\u30fc\u30c9\u304c\u30e1\u30fc\u30eb\u30b5\u30fc\u30d0\u30fc\u304c\u65e2\u306b\u5229\u7528\u3057\u3066\u3044\u308b\u30ec\u30b3\u30fc\u30c9\u3068\u7af6\u5408\u3059\u308b\u3053\u3068\u306f\u3042\u308a\u307e\u305b\u3093\u3002\u4e21\u65b9\u306e\u30eb\u30fc\u30c8\u304c\u540c\u6642\u306b\u5b8c\u5168\u306b\u8a8d\u8a3c\u3055\u308c\u305f\u72b6\u614b\u3092\u7dad\u6301\u3059\u308b\u305f\u3081\u3001\u5206\u5272\u8a2d\u5b9a\u304c\u5b89\u5168\u306b\u306a\u308a\u307e\u3059\u3002<\/p>\n\n\n\n<h2 id=\"how-to-confirm-the-smtp-relay-is-really-in-use\" class=\"wp-block-heading\">SMTP\u30ea\u30ec\u30fc\u304c\u5b9f\u969b\u306b\u4f7f\u7528\u3055\u308c\u3066\u3044\u308b\u3053\u3068\u3092\u78ba\u8a8d\u3059\u308b\u65b9\u6cd5<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\u30eb\u30fc\u30eb\u3092\u6700\u521d\u306b\u4fdd\u5b58\u3057\u305f\u969b\u306b\u8aa4\u308a\u304c\u3042\u308a\u3001\u753b\u9762\u306b\u306f\u4f55\u3082\u8868\u793a\u3055\u308c\u307e\u305b\u3093\u3067\u3057\u305f\u3002\u4ed6\u306e\u30d5\u30a3\u30fc\u30eb\u30c9\u306b\u5165\u529b\u3057\u3066\u3044\u308b\u9593\u306b\u3001\u30d6\u30e9\u30a6\u30b6\u306e\u30d1\u30b9\u30ef\u30fc\u30c9\u30de\u30cd\u30fc\u30b8\u30e3\u30fc\u304c\u30d1\u30b9\u30ef\u30fc\u30c9\u6b04\u306bDSM\u306e\u30ed\u30b0\u30a4\u30f3\u30d1\u30b9\u30ef\u30fc\u30c9\u3092\u81ea\u52d5\u5165\u529b\u3057\u3066\u3057\u307e\u3044\u3001\u30d5\u30a9\u30fc\u30e0\u306f\u305d\u308c\u3092\u554f\u984c\u306a\u304f\u53d7\u3051\u5165\u308c\u3066\u3057\u307e\u3044\u307e\u3057\u305f\u3002\u672c\u6765\u3067\u3042\u308c\u3070\u3001\u8a72\u5f53\u30c9\u30e1\u30a4\u30f3\u3078\u306e\u30e1\u30c3\u30bb\u30fc\u30b8\u306f\u8a8d\u8a3c\u30a8\u30e9\u30fc\u3068\u3057\u3066\u30ad\u30e5\u30fc\u306b\u6ede\u7559\u3057\u3066\u3044\u305f\u306f\u305a\u3067\u3059\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u9867\u5ba2\u304c\u30a2\u30af\u30bb\u30b9\u3059\u308b\u524d\u306b\u3001SMTP\u30ea\u30ec\u30fc\u304c\u6b63\u5e38\u306b\u6a5f\u80fd\u3057\u3066\u3044\u308b\u304b\u3069\u3046\u304b\u30923\u3064\u306e\u30c1\u30a7\u30c3\u30af\u3067\u78ba\u8a8d\u3067\u304d\u307e\u3059\u3002<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>\u30ad\u30fc\u3092\u6700\u5f8c\u306b\u8cbc\u308a\u4ed8\u3051\u3066\u3001\u305d\u306e\u9577\u3055\u3092\u78ba\u8a8d\u3057\u3066\u304f\u3060\u3055\u3044\u3002<\/strong> \u518d\u9001\u4fe1\u30ad\u30fc\u306f\u4ee5\u4e0b\u3067\u59cb\u307e\u308a\u307e\u3059 <code>\u518d_<\/code> \u6587\u5b57\u6570\u306f36\u6587\u5b57\u3067\u3059\u3002\u77ed\u3044\u30c9\u30c3\u30c8\u306e\u5217\u306f\u3001\u30d6\u30e9\u30a6\u30b6\u304c\u5225\u306e\u6587\u5b57\u3092\u5165\u529b\u3057\u305f\u3053\u3068\u3092\u610f\u5473\u3057\u307e\u3059\u3002<\/li>\n\n\n\n<li><strong>\u5217\u306b\u4e26\u3093\u3067\u304f\u3060\u3055\u3044\u3002<\/strong> \u30c6\u30b9\u30c8\u30e1\u30c3\u30bb\u30fc\u30b8\u9001\u4fe1\u5f8c\u3001MailPlus\u30b5\u30fc\u30d0\u30fc\u306e\u30ad\u30e5\u30fc\u30da\u30fc\u30b8\u306f\u7a7a\u306b\u306a\u3063\u3066\u3044\u308b\u306f\u305a\u3067\u3059\u3002\u305d\u3053\u306b\u8868\u793a\u3055\u308c\u308b\u9045\u5ef6\u30e1\u30c3\u30bb\u30fc\u30b8\u306b\u306f\u3001SMTP\u30ea\u30ec\u30fc\u304c\u8fd4\u3057\u305f\u7406\u7531\u304c\u793a\u3055\u308c\u3066\u3044\u307e\u3059\u3002<\/li>\n\n\n\n<li><strong>\u9375\u306b\u6ce8\u76ee\u3057\u3066\u304f\u3060\u3055\u3044\u3002<\/strong> \u300cAPI\u30ad\u30fc\u306e\u518d\u9001\u4fe1\u300d\u30da\u30fc\u30b8\u306e\u300c\u6700\u5f8c\u306b\u4f7f\u7528\u3055\u308c\u305f\u5217\u300d\u306b\u306f\u3001\u6700\u521d\u306e\u30e1\u30c3\u30bb\u30fc\u30b8\u304c\u6b63\u5e38\u306b\u8a8d\u8a3c\u3055\u308c\u308b\u307e\u3067\u30a2\u30af\u30c6\u30a3\u30d3\u30c6\u30a3\u306f\u767a\u751f\u3057\u306a\u3044\u3068\u8868\u793a\u3055\u308c\u307e\u3059\u3002<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">\u30e1\u30fc\u30eb\u30b5\u30fc\u30d0\u30fc\u306b\u63a5\u7d9a\u3059\u308b\u524d\u306b\u3001SMTP\u30ea\u30ec\u30fc\u3092\u76f4\u63a5\u30c6\u30b9\u30c8\u3059\u308b\u305f\u3081\u3001\u81ea\u793e\u306e\u30e1\u30fc\u30eb\u30dc\u30c3\u30af\u30b9\u306bSMTP\u7d4c\u7531\u3067\u30e1\u30c3\u30bb\u30fc\u30b8\u3092\u9001\u4fe1\u3057\u307e\u3057\u305f\u3002\u305d\u306e\u7d50\u679c\u3001SPF\u3001DKIM\u3001DMARC\u304c\u30c9\u30e1\u30a4\u30f3\u306b\u5bfe\u3057\u3066\u6b63\u5e38\u306b\u901a\u904e\u3057\u3001\u82f1\u8a9e\u4ee5\u5916\u306e\u4ef6\u540d\u3001\u30d7\u30ec\u30fc\u30f3\u30c6\u30ad\u30b9\u30c8\u90e8\u5206\u3092\u542b\u3080HTML\u672c\u6587\u3001PDF\u6dfb\u4ed8\u30d5\u30a1\u30a4\u30eb\u3001\u30ab\u30b9\u30bf\u30e0\u30d8\u30c3\u30c0\u30fc\u3082\u3059\u3079\u3066\u7121\u50b7\u3067\u5c4a\u304d\u307e\u3057\u305f\u3002\u3064\u307e\u308a\u3001SMTP\u30ea\u30ec\u30fc\u306f\u901a\u5e38\u306e\u30e1\u30c3\u30bb\u30fc\u30b8\u30b3\u30f3\u30c6\u30f3\u30c4\u3092\u640d\u306a\u3046\u3053\u3068\u306f\u3042\u308a\u307e\u305b\u3093\u3002\u6ce8\u6587\u78ba\u8a8d\u30e1\u30fc\u30eb\u309216\u8a00\u8a9e\u3067\u9001\u4fe1\u3059\u308b\u5e97\u8217\u306b\u3068\u3063\u3066\u3001\u3053\u308c\u306f\u91cd\u8981\u306a\u70b9\u3067\u3059\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u305d\u3057\u3066\u3001\u3044\u3088\u3044\u3088\u91cd\u8981\u306a\u30c6\u30b9\u30c8\u306e\u65e5\u304c\u3084\u3063\u3066\u304d\u307e\u3057\u305f\u300210\u670811\u65e5\u3001\u30d9\u30eb\u30ae\u30fc\u306e\u304a\u5ba2\u69d8\u306b\u6ce8\u6587\u78ba\u8a8d\u30e1\u30fc\u30eb\u3092\u518d\u5ea6\u9001\u4fe1\u3057\u307e\u3057\u305f\u3002\u3053\u308c\u306f2\u65e5\u524d\u306b\u9001\u4fe1\u30a8\u30e9\u30fc\u306b\u306a\u3063\u305f\u306e\u3068\u540c\u3058\u30e1\u30fc\u30eb\u3067\u3059\u3002\u30e1\u30fc\u30eb\u30ed\u30b0\u306b\u306f\u3001MailPlus\u30b5\u30fc\u30d0\u30fc\u304c\u30ad\u30e5\u30fc\u306b\u5165\u3063\u3066\u304b\u30893.2\u79d2\u5f8c\u306b\u30e1\u30fc\u30eb\u3092\u8ee2\u9001\u3057\u305f\u3053\u3068\u304c\u8a18\u9332\u3055\u308c\u3066\u304a\u308a\u3001\u30c0\u30c3\u30b7\u30e5\u30dc\u30fc\u30c9\u306b\u306f\u300c\u914d\u4fe1\u6e08\u307f\u300d\u3068\u8868\u793a\u3055\u308c\u3066\u3044\u307e\u3057\u305f\u3002\u3053\u308c\u306f\u3001\u30d7\u30ed\u30d0\u30a4\u30c0\u306e\u30b5\u30fc\u30d0\u30fc\u304c\u30e1\u30c3\u30bb\u30fc\u30b8\u3092\u62d2\u5426\u3059\u308b\u306e\u3067\u306f\u306a\u304f\u3001\u53d7\u3051\u5165\u308c\u305f\u3053\u3068\u3092\u610f\u5473\u3057\u307e\u3059\u3002<\/p>\n\n\n\n<figure class=\"wp-block-image size-full\"><img decoding=\"async\" width=\"1134\" height=\"268\" sizes=\"(max-width: 1134px) 100vw, 1134px\" src=\"https:\/\/synopower.club\/wp-content\/uploads\/2026\/10\/resend-email-delivered-telenet.webp\" alt=\"\u6ce8\u6587\u30e1\u30fc\u30eb\u304cSMTP\u30ea\u30ec\u30fc\u7d4c\u7531\u3067\u62d2\u5426\u3057\u305f\u30d7\u30ed\u30d0\u30a4\u30c0\u30fc\u306b\u914d\u4fe1\u3055\u308c\u305f\u3053\u3068\u3092\u793a\u3059\u518d\u9001\u4fe1\u30c0\u30c3\u30b7\u30e5\u30dc\u30fc\u30c9\" class=\"wp-image-21893\" srcset=\"https:\/\/synopower.club\/wp-content\/uploads\/2026\/10\/resend-email-delivered-telenet.webp 1134w, https:\/\/synopower.club\/wp-content\/uploads\/2026\/10\/resend-email-delivered-telenet-300x71.webp 300w, https:\/\/synopower.club\/wp-content\/uploads\/2026\/10\/resend-email-delivered-telenet-1024x242.webp 1024w, https:\/\/synopower.club\/wp-content\/uploads\/2026\/10\/resend-email-delivered-telenet-768x182.webp 768w, https:\/\/synopower.club\/wp-content\/uploads\/2026\/10\/resend-email-delivered-telenet-18x4.webp 18w, https:\/\/synopower.club\/wp-content\/uploads\/2026\/10\/resend-email-delivered-telenet-400x95.webp 400w, https:\/\/synopower.club\/wp-content\/uploads\/2026\/10\/resend-email-delivered-telenet-1000x236.webp 1000w\" \/><figcaption class=\"wp-element-caption\">10\u67089\u65e5\u306b\u62d2\u5426\u3055\u308c\u305f\u6ce8\u6587\u30e1\u30fc\u30eb\u304c\u300110\u670811\u65e5\u306b\u627f\u8a8d\u3055\u308c\u305f\u3082\u306e\u3067\u3059\u3002\u3053\u306e\u30b9\u30af\u30ea\u30fc\u30f3\u30b7\u30e7\u30c3\u30c8\u3067\u306f\u3001\u9867\u5ba2\u306e\u4f4f\u6240\u306f\u5909\u66f4\u3055\u308c\u3066\u3044\u307e\u3059\u3002<\/figcaption><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">1\u3064\u306e\u30e1\u30c3\u30bb\u30fc\u30b8\u306f\u7d50\u679c\u3067\u3042\u3063\u3066\u3001\u7d71\u8a08\u3067\u306f\u3042\u308a\u307e\u305b\u3093\u3002\u300c\u914d\u4fe1\u6e08\u307f\u300d\u306f\u53d7\u4fe1\u30b5\u30fc\u30d0\u30fc\u304c\u300c\u306f\u3044\u300d\u3068\u5fdc\u7b54\u3057\u305f\u3053\u3068\u3092\u793a\u3059\u3060\u3051\u3067\u3001\u30e1\u30c3\u30bb\u30fc\u30b8\u304c\u3069\u306e\u30d5\u30a9\u30eb\u30c0\u306b\u4fdd\u5b58\u3055\u308c\u305f\u304b\u306f\u308f\u304b\u308a\u307e\u305b\u3093\u3002\u4eca\u5f8c\u3001\u3055\u3089\u306b\u591a\u304f\u306e\u30c9\u30e1\u30a4\u30f3\u3092\u79fb\u884c\u3059\u308b\u524d\u306b\u3001\u3053\u308c\u3089\u306e\u30d7\u30ed\u30d0\u30a4\u30c0\u30fc\u3078\u306e\u5b9f\u969b\u306e\u6ce8\u6587\u72b6\u6cc1\u3092\u7d99\u7d9a\u7684\u306b\u76e3\u8996\u3057\u3066\u3044\u304d\u307e\u3059\u3002<\/p>\n\n\n\n<h2 id=\"what-resend-rewrites-in-your-messages\" class=\"wp-block-heading\">\u30e1\u30c3\u30bb\u30fc\u30b8\u306e\u518d\u9001\u4fe1\u30ea\u30e9\u30a4\u30c8\u3068\u306f<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\u30e1\u30c3\u30bb\u30fc\u30b8\u3092\u518d\u69cb\u7bc9\u3059\u308bSMTP\u30ea\u30ec\u30fc\u306f\u900f\u904e\u7684\u306a\u30d1\u30a4\u30d7\u3067\u306f\u306a\u3044\u305f\u3081\u3001\u91cd\u8981\u306a\u30c7\u30fc\u30bf\u3092\u30eb\u30fc\u30c6\u30a3\u30f3\u30b0\u3059\u308b\u524d\u306b\u305d\u306e\u9055\u3044\u3092\u7406\u89e3\u3057\u3066\u304a\u304f\u3053\u3068\u304c\u91cd\u8981\u3067\u3059\u3002\u9001\u4fe1\u3057\u305f\u30c7\u30fc\u30bf\u3068\u53d7\u4fe1\u3057\u305f\u30c7\u30fc\u30bf\u3092\u6bd4\u8f03\u3057\u305f\u3068\u3053\u308d\u30014\u3064\u306e\u5909\u66f4\u70b9\u304c\u898b\u3064\u304b\u308a\u307e\u3057\u305f\u3002<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>\u300c\u5b9b\u5148\u300d\u30d8\u30c3\u30c0\u30fc\u306f\u3001\u552f\u4e00\u306e\u53d7\u4fe1\u8005\u3068\u306a\u308a\u307e\u3059\u3002<\/strong> \u5404\u53d7\u53d6\u4eba\u306b\u306f\u81ea\u5206\u5b9b\u3066\u306e\u30b3\u30d4\u30fc\u304c\u9001\u4ed8\u3055\u308c\u308b\u305f\u3081\u3001\u5143\u306e\u53d7\u53d6\u4eba\u30ea\u30b9\u30c8\u306f\u3082\u306f\u3084\u898b\u3048\u306a\u304f\u306a\u308a\u307e\u3059\u3002<\/li>\n\n\n\n<li><strong>\u30e1\u30c3\u30bb\u30fc\u30b8ID\u304c\u7f6e\u304d\u63db\u3048\u3089\u308c\u307e\u3059\u3002<\/strong> \u30e1\u30fc\u30eb\u30af\u30e9\u30a4\u30a2\u30f3\u30c8\u306f\u305d\u306e\u5024\u3092\u4f7f\u7528\u3057\u3066\u8fd4\u4fe1\u3092\u30b0\u30eb\u30fc\u30d7\u5316\u3057\u3001\u30b9\u30ec\u30c3\u30c9\u3092\u5206\u5272\u3067\u304d\u308b\u3088\u3046\u306b\u3057\u307e\u3059\u3002<\/li>\n\n\n\n<li><strong>\u65e5\u4ed8\u30d8\u30c3\u30c0\u30fc\u306fUTC\u306b\u5909\u63db\u3055\u308c\u307e\u3059\u3002<\/strong> \u6642\u523b\u306f\u540c\u3058\u3060\u304c\u3001\u8868\u793a\u3055\u308c\u308b\u30bf\u30a4\u30e0\u30be\u30fc\u30f3\u304c\u7570\u306a\u308b\u3002<\/li>\n\n\n\n<li><strong>\u3054\u81ea\u8eab\u306e\u30b5\u30fc\u30d0\u30fc\u304b\u3089\u53d7\u4fe1\u3057\u305f\u884c\u306f\u524a\u9664\u3055\u308c\u307e\u3059\u3002<\/strong> \u53d7\u4fe1\u8005\u306f\u5185\u90e8\u7d4c\u8def\u3092\u78ba\u8a8d\u3067\u304d\u306a\u304f\u306a\u308a\u307e\u3057\u305f\u3002<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">\u6ce8\u6587\u78ba\u8a8d\u30e1\u30fc\u30eb\u3092\u9867\u5ba21\u4eba\u306b\u9001\u4fe1\u3059\u308b\u5834\u5408\u3001\u3053\u308c\u3089\u306e\u3053\u3068\u306f\u4f55\u3089\u554f\u984c\u306b\u306a\u308a\u307e\u305b\u3093\u3002\u3057\u304b\u3057\u30013\u4eba\u304cCC\u3067\u3084\u308a\u53d6\u308a\u3059\u308b\u30e1\u30fc\u30eb\u306e\u5834\u5408\u306f\u975e\u5e38\u306b\u91cd\u8981\u3067\u3042\u308a\u3001SMTP\u30ea\u30ec\u30fc\u306b\u3059\u3079\u3066\u306e\u30c9\u30e1\u30a4\u30f3\u3067\u306f\u306a\u304f\u3001\u9078\u629e\u3057\u305f\u30c9\u30e1\u30a4\u30f3\u306e\u307f\u3092\u767b\u9332\u3059\u3079\u304d\u3067\u3042\u308b\u3068\u3044\u3046\u6700\u3082\u5f37\u529b\u306a\u6839\u62e0\u3068\u306a\u308a\u307e\u3059\u3002<\/p>\n\n\n\n<h2 id=\"why-our-mail-still-lives-on-synology-mailplus\" class=\"wp-block-heading\">\u306a\u305c\u79c1\u305f\u3061\u306e\u30e1\u30fc\u30eb\u306f\u4eca\u3082Synology MailPlus\u3067\u751f\u304d\u7d9a\u3051\u3066\u3044\u308b\u306e\u304b<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">2 \u3064\u306e\u30c9\u30e1\u30a4\u30f3\u306b\u5916\u90e8 SMTP \u30ea\u30ec\u30fc\u3092\u8ffd\u52a0\u3057\u3066\u3082\u3001\u30e1\u30fc\u30eb\u306e\u4fdd\u5b58\u5834\u6240\u306f\u5909\u308f\u308a\u307e\u305b\u3093\u3002\u3059\u3079\u3066\u306e\u30e1\u30fc\u30eb\u30dc\u30c3\u30af\u30b9\u3001\u3059\u3079\u3066\u306e\u9001\u4fe1\u30e1\u30c3\u30bb\u30fc\u30b8\u3001\u3059\u3079\u3066\u306e\u914d\u4fe1\u30ed\u30b0\u306f\u3001\u5f15\u304d\u7d9a\u304d\u5f53\u793e\u306e NAS \u4e0a\u306b\u3042\u308a\u3001 <a href=\"https:\/\/synopower.club\/ja\/synology-mailplus-5%e3%82%a2%e3%82%ab%e3%82%a6%e3%83%b3%e3%83%88\/\" target=\"_blank\" rel=\"noreferrer noopener\">Synology MailPlus<\/a> \u4f9d\u7136\u3068\u3057\u3066\u3001\u30e1\u30c3\u30bb\u30fc\u30b8\u3054\u3068\u306b\u3069\u306e\u7d4c\u8def\u3092\u9078\u629e\u3059\u308b\u304b\u3092\u6c7a\u5b9a\u3057\u3066\u3044\u307e\u3059\u3002\u30db\u30b9\u30c6\u30a3\u30f3\u30b0\u578b\u306e\u30e1\u30fc\u30eb\u30b9\u30a4\u30fc\u30c8\u3067\u306f\u3001\u305d\u306e\u3088\u3046\u306a\u9078\u629e\u80a2\u306f\u5f97\u3089\u308c\u307e\u305b\u3093\u3002\u9001\u4fe1\u7d4c\u8def\u306f\u30d9\u30f3\u30c0\u30fc\u306e\u7d4c\u8def\u306e\u307f\u3068\u306a\u308a\u3001\u554f\u984c\u304c\u767a\u751f\u3057\u305f\u5834\u5408\u306b\u56de\u907f\u3059\u308b\u305f\u3081\u306e\u30eb\u30fc\u30eb\u3082\u5b58\u5728\u3057\u307e\u305b\u3093\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u305d\u306e\u305f\u3081\u3001\u4fee\u6b63\u8cbb\u7528\u306f\u4e00\u5207\u304b\u304b\u308a\u307e\u305b\u3093\u3002\u30b5\u30fc\u30d0\u30fc\u306b\u306f5\u3064\u306e\u30e1\u30fc\u30eb\u30a2\u30ab\u30a6\u30f3\u30c8\u304c\u7121\u6599\u3067\u542b\u307e\u308c\u3066\u304a\u308a\u3001\u8ffd\u52a0\u306e\u30e9\u30a4\u30bb\u30f3\u30b9\u306f\u6708\u984d\u30ec\u30f3\u30bf\u30eb\u3067\u306f\u306a\u304f\u4e00\u62ec\u8cfc\u5165\u3067\u6e08\u307f\u3001SMTP\u30ea\u30ec\u30fc\u30eb\u30fc\u30eb\u3082\u30d1\u30c3\u30b1\u30fc\u30b8\u306b\u542b\u307e\u308c\u3066\u3044\u307e\u3059\u3002\u3054\u81ea\u8eab\u3067\u30e1\u30fc\u30eb\u3092\u904b\u7528\u3059\u308b\u3053\u3068\u3092\u691c\u8a0e\u3055\u308c\u3066\u3044\u308b\u5834\u5408\u306f\u3001\u5f0a\u793e\u306e\u30ac\u30a4\u30c9\u306b\u8a73\u7d30\u304c\u8a18\u8f09\u3055\u308c\u3066\u3044\u307e\u3059\u306e\u3067\u3001\u305d\u3061\u3089\u3092\u3054\u89a7\u304f\u3060\u3055\u3044\u3002 <a href=\"https:\/\/synopower.club\/ja\/synology-mailplus-mail-server-guide\/\">Synology MailPlus\u30e1\u30fc\u30eb\u30b5\u30fc\u30d0\u30fc\u30ac\u30a4\u30c9<\/a>.<\/p>\n\n\n\n<div class=\"wp-block-buttons is-content-justification-center is-layout-flex wp-container-core-buttons-is-layout-a221f4eb wp-block-buttons-is-layout-flex\" style=\"border-style:none;border-width:0px;border-radius:0px;margin-top:var(--wp--preset--spacing--50);margin-bottom:var(--wp--preset--spacing--50);padding-top:var(--wp--preset--spacing--40);padding-right:0;padding-bottom:var(--wp--preset--spacing--40);padding-left:0\">\n<div class=\"wp-block-button is-style-fill\"><a class=\"wp-block-button__link has-palette-color-4-color has-luminous-vivid-amber-background-color has-text-color has-background has-link-color wp-element-button\" href=\"https:\/\/synopower.club\/ja\/synology-mailplus-5%e3%82%a2%e3%82%ab%e3%82%a6%e3%83%b3%e3%83%88\/\" style=\"border-radius:15px\" target=\"_blank\" rel=\"noreferrer noopener\">MailPlus\u30e9\u30a4\u30bb\u30f3\u30b9\u3092\u53d6\u5f97\u3059\u308b<\/a><\/div>\n<\/div>\n\n\n\n<h2 id=\"smtp-relay-limits-and-caveats\" class=\"wp-block-heading\">SMTP\u30ea\u30ec\u30fc\u306e\u5236\u9650\u4e8b\u9805\u3068\u6ce8\u610f\u4e8b\u9805<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">SMTP\u30ea\u30ec\u30fc\u306f\u7279\u5b9a\u306e\u554f\u984c\u3092\u89e3\u6c7a\u3059\u308b\u4e00\u65b9\u3067\u3001\u3044\u304f\u3064\u304b\u306e\u65b0\u305f\u306a\u554f\u984c\u3082\u5f15\u304d\u8d77\u3053\u3057\u307e\u3059\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u304a\u5ba2\u69d8\u304c\u3053\u306e\u30b5\u30fc\u30d3\u30b9\u3092\u7d4c\u7531\u3057\u3066\u9001\u4fe1\u3059\u308b\u30e1\u30c3\u30bb\u30fc\u30b8\u306f\u3001\u7b2c\u4e09\u8005\u306b\u3088\u3063\u3066\u51e6\u7406\u3055\u308c\u307e\u3059\u3002\u5f0a\u793e\u306e\u30e1\u30c3\u30bb\u30fc\u30b8\u306b\u306f\u30e9\u30a4\u30bb\u30f3\u30b9\u30ad\u30fc\u304c\u542b\u307e\u308c\u3066\u3044\u308b\u305f\u3081\u3001\u30c9\u30e1\u30a4\u30f3\u30ea\u30b9\u30c8\u3092\u77ed\u304f\u3057\u3001\u9001\u4fe1\u306e\u307f\u53ef\u80fd\u306a\u30ad\u30fc\u3092\u4f7f\u7528\u3057\u3066\u3044\u307e\u3059\u3002\u7279\u306b\u6b27\u5dde\u9023\u5408\u306e\u304a\u5ba2\u69d8\u5b9b\u3066\u306e\u30e1\u30fc\u30eb\u3092\u5916\u90e8\u30b5\u30fc\u30d3\u30b9\u7d4c\u7531\u3067\u9001\u4fe1\u3059\u308b\u524d\u306b\u3001\u304a\u5ba2\u69d8\u81ea\u8eab\u306e\u30d7\u30e9\u30a4\u30d0\u30b7\u30fc\u30dd\u30ea\u30b7\u30fc\u3092\u3054\u78ba\u8a8d\u304f\u3060\u3055\u3044\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u7121\u6599\u30d7\u30e9\u30f3\u306b\u306f1\u65e5\u306e\u9001\u4fe1\u4e0a\u9650\u304c\u3042\u308a\u307e\u3059\u3002\u4e00\u90e8\u306e\u30c9\u30e1\u30a4\u30f3\u3067\u306f1\u65e5100\u901a\u306e\u9001\u4fe1\u306f\u5341\u5206\u306a\u4e0a\u9650\u3067\u3059\u304c\u3001\u9867\u5ba2\u30ea\u30b9\u30c8\u5168\u4f53\u306b\u30e1\u30fc\u30eb\u3092\u9001\u4fe1\u3059\u308b\u3068\u6570\u5206\u3067\u4e0a\u9650\u306b\u9054\u3057\u3066\u3057\u307e\u3044\u307e\u3059\u3002\u30cb\u30e5\u30fc\u30b9\u30ec\u30bf\u30fc\u306f\u5225\u306e\u30d7\u30e9\u30f3\u3001\u7406\u60f3\u7684\u306b\u306f\u5225\u306e\u30b5\u30d6\u30c9\u30e1\u30a4\u30f3\u3067\u914d\u4fe1\u3059\u308b\u3053\u3068\u3092\u304a\u52e7\u3081\u3057\u307e\u3059\u3002\u305d\u3046\u3059\u308b\u3053\u3068\u3067\u3001\u30de\u30fc\u30b1\u30c6\u30a3\u30f3\u30b0\u306b\u95a2\u3059\u308b\u82e6\u60c5\u304c\u6ce8\u6587\u30e1\u30fc\u30eb\u306e\u8a55\u5224\u306b\u5f71\u97ff\u3092\u4e0e\u3048\u308b\u3053\u3068\u3092\u9632\u3050\u3053\u3068\u304c\u3067\u304d\u307e\u3059\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u8a55\u5224\u306f\u501f\u308a\u7269\u3067\u3042\u308a\u3001\u6240\u6709\u3059\u308b\u3082\u306e\u3067\u306f\u3042\u308a\u307e\u305b\u3093\u3002\u5171\u6709\u9001\u4fe1\u30a2\u30c9\u30ec\u30b9\u306f\u9069\u5207\u306b\u7ba1\u7406\u3055\u308c\u307e\u3059\u304c\u3001\u4ed6\u306e\u30e6\u30fc\u30b6\u30fc\u304c\u305d\u308c\u3092\u4f7f\u7528\u3059\u308b\u304b\u3069\u3046\u304b\u306f\u5236\u5fa1\u3067\u304d\u307e\u305b\u3093\u3002\u5909\u66f4\u5f8c\u3082\u30d7\u30ed\u30d0\u30a4\u30c0\u304b\u3089\u62d2\u5426\u3055\u308c\u308b\u5834\u5408\u306f\u3001\u7d4c\u8def\u306b\u554f\u984c\u304c\u3042\u308b\u3068\u6c7a\u3081\u3064\u3051\u308b\u524d\u306b\u3001\u30c0\u30c3\u30b7\u30e5\u30dc\u30fc\u30c9\u306e\u30d0\u30a6\u30f3\u30b9\u30e1\u30c3\u30bb\u30fc\u30b8\u3092\u78ba\u8a8d\u3057\u3066\u304f\u3060\u3055\u3044\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u6700\u5f8c\u306b\u3001\u30c1\u30e3\u30c3\u30c8\u3001\u30c1\u30b1\u30c3\u30c8\u3001\u307e\u305f\u306f\u30b9\u30af\u30ea\u30fc\u30f3\u30b7\u30e7\u30c3\u30c8\u306b\u8cbc\u308a\u4ed8\u3051\u3089\u308c\u305fAPI\u30ad\u30fc\u306f\u7f6e\u304d\u63db\u3048\u308b\u5fc5\u8981\u304c\u3042\u308a\u307e\u3059\u3002\u65b0\u3057\u3044\u30ad\u30fc\u3092\u4f5c\u6210\u3057\u3001SMTP\u30ea\u30ec\u30fc\u30eb\u30fc\u30eb\u3092\u66f4\u65b0\u3057\u3001\u30c6\u30b9\u30c8\u3092\u9001\u4fe1\u3057\u3066\u3001\u53e4\u3044\u30ad\u30fc\u3092\u524a\u9664\u3057\u3066\u304f\u3060\u3055\u3044\u3002\u305f\u3063\u305f2\u5206\u3067\u3001\u4f55\u5e74\u3082\u7d9a\u304f\u53ef\u80fd\u6027\u306e\u3042\u308b\u30ea\u30b9\u30af\u3092\u89e3\u6d88\u3067\u304d\u307e\u3059\u3002<\/p>\n\n\n\n<h2 id=\"frequently-asked-questions\" class=\"wp-block-heading\">\u3088\u304f\u3042\u308b\u8cea\u554f<\/h2>\n\n\n<div id=\"rank-math-faq\" class=\"rank-math-block\">\n<div class=\"rank-math-list\">\n<div id=\"faq-1\" class=\"rank-math-list-item\">\n<h3 class=\"rank-math-question\">SMTP\u30ea\u30ec\u30fc\u3068\u306f\u4f55\u3067\u3059\u304b\uff1f<\/h3>\n<div class=\"rank-math-answer\">\n\n<p>SMTP\u30ea\u30ec\u30fc\u3068\u306f\u3001\u3042\u306a\u305f\u306e\u30b5\u30fc\u30d0\u30fc\u304b\u3089\u30e1\u30c3\u30bb\u30fc\u30b8\u3092\u53d7\u3051\u53d6\u308a\u3001\u3042\u306a\u305f\u306b\u4ee3\u308f\u3063\u3066\u914d\u4fe1\u3059\u308b\u30e1\u30fc\u30eb\u30b5\u30fc\u30d0\u30fc\u306e\u3053\u3068\u3067\u3059\u3002\u53d7\u4fe1\u5074\u306f\u3001\u3042\u306a\u305f\u306e\u30b5\u30fc\u30d0\u30fc\u304c\u9001\u4fe1\u3057\u305f\u30a2\u30c9\u30ec\u30b9\u3067\u306f\u306a\u304f\u3001\u30ea\u30ec\u30fc\u306e\u8a55\u5224\u306b\u57fa\u3065\u3044\u3066\u30e1\u30c3\u30bb\u30fc\u30b8\u3092\u5224\u65ad\u3057\u307e\u3059\u3002<\/p>\n\n<\/div>\n<\/div>\n<div id=\"faq-2\" class=\"rank-math-list-item\">\n<h3 class=\"rank-math-question\">SPF\u3001DKIM\u3001DMARC\u304c\u3059\u3079\u3066\u901a\u904e\u3057\u3066\u3044\u308b\u306b\u3082\u304b\u304b\u308f\u3089\u305a\u3001\u79c1\u306eSynology NAS\u304b\u3089\u306e\u30e1\u30fc\u30eb\u304c\u30b9\u30d1\u30e0\u30d5\u30a9\u30eb\u30c0\u306b\u632f\u308a\u5206\u3051\u3089\u308c\u308b\u306e\u306f\u306a\u305c\u3067\u3059\u304b\uff1f<\/h3>\n<div class=\"rank-math-answer\">\n\n<p>\u3053\u308c\u30893\u3064\u306e\u30c1\u30a7\u30c3\u30af\u306b\u3088\u3063\u3066\u3001\u30e1\u30c3\u30bb\u30fc\u30b8\u304c\u672c\u5f53\u306b\u3042\u306a\u305f\u306e\u30c9\u30e1\u30a4\u30f3\u304b\u3089\u9001\u4fe1\u3055\u308c\u305f\u3082\u306e\u3067\u3042\u308b\u3053\u3068\u304c\u8a3c\u660e\u3055\u308c\u307e\u3059\u3002\u53d7\u4fe1\u5074\u3067\u306f\u3001\u30e1\u30c3\u30bb\u30fc\u30b8\u3092\u9001\u4fe1\u3057\u305fIP\u30a2\u30c9\u30ec\u30b9\u3082\u8a55\u4fa1\u3055\u308c\u307e\u3059\u3002\u6c4e\u7528\u7684\u306a\u9006\u5f15\u304dDNS\u540d\u3084\u3001\u5c65\u6b74\u304c\u6df7\u5728\u3059\u308b\u5171\u6709\u9001\u4fe1\u30b5\u30fc\u30d0\u30fc\u306f\u3001\u3053\u306e2\u3064\u76ee\u306e\u30c6\u30b9\u30c8\u306b\u5358\u72ec\u3067\u4e0d\u5408\u683c\u3068\u306a\u308b\u53ef\u80fd\u6027\u304c\u3042\u308a\u307e\u3059\u3002<\/p>\n\n<\/div>\n<\/div>\n<div id=\"faq-3\" class=\"rank-math-list-item\">\n<h3 class=\"rank-math-question\">Synology MailPlus\u306f\u3001\u7279\u5b9a\u306e\u30c9\u30e1\u30a4\u30f3\u306e\u307f\u3092\u5bfe\u8c61\u3068\u3057\u305fSMTP\u30ea\u30ec\u30fc\u3092\u30b5\u30dd\u30fc\u30c8\u3057\u3066\u3044\u307e\u3059\u304b\uff1f<\/h3>\n<div class=\"rank-math-answer\">\n\n<p>\u306f\u3044\u3002\u30e1\u30fc\u30eb\u914d\u4fe1\u3001\u30ea\u30ec\u30fc\u8a2d\u5b9a\u3001\u4f8b\u5916\u30eb\u30fc\u30eb\u3067\u53d7\u4fe1\u8005\u30eb\u30fc\u30eb\u3092\u4f5c\u6210\u3067\u304d\u307e\u3059\u3002\u5404\u30eb\u30fc\u30eb\u306f\u500b\u5225\u306eSMTP\u30ea\u30ec\u30fc\u3068\u3057\u3066\u6a5f\u80fd\u3057\u307e\u3059\u3002\u5404\u30eb\u30fc\u30eb\u306b\u306f\u72ec\u81ea\u306e\u30b5\u30fc\u30d0\u30fc\u3001\u30dd\u30fc\u30c8\u3001\u8a8d\u8a3c\u60c5\u5831\u304c\u3042\u308a\u3001\u305d\u306e\u30ea\u30b9\u30c8\u306b\u542b\u307e\u308c\u308b\u30c9\u30e1\u30a4\u30f3\u307e\u305f\u306f\u30a2\u30c9\u30ec\u30b9\u306b\u306e\u307f\u9069\u7528\u3055\u308c\u307e\u3059\u3002<\/p>\n\n<\/div>\n<\/div>\n<div id=\"faq-4\" class=\"rank-math-list-item\">\n<h3 class=\"rank-math-question\">Resend\u306fSMTP\u30ea\u30ec\u30fc\u3068\u3057\u3066\u7121\u6599\u3067\u5229\u7528\u3067\u304d\u307e\u3059\u304b\uff1f<\/h3>\n<div class=\"rank-math-answer\">\n\n<p>\u79c1\u305f\u3061\u304c2026\u5e7410\u6708\u306b\u5951\u7d04\u3057\u305f\u6642\u70b9\u3067\u306f\u3001\u7121\u6599\u30d7\u30e9\u30f3\u3067\u306f\u6708\u95933,000\u901a\u30011\u65e5100\u901a\u306e\u30e1\u30fc\u30eb\u9001\u4fe1\u30683\u3064\u306e\u30c9\u30e1\u30a4\u30f3\u304c\u5229\u7528\u53ef\u80fd\u3067\u3057\u305f\u3002\u3053\u308c\u306f\u5c0f\u898f\u6a21\u5e97\u8217\u306e\u53d6\u5f15\u30e1\u30fc\u30eb\u306b\u306f\u5341\u5206\u3067\u3042\u308a\u3001\u7279\u306b\u4e00\u90e8\u306e\u30c9\u30e1\u30a4\u30f3\u306e\u307f\u3092\u4f7f\u7528\u3059\u308b\u5834\u5408\u306f\u306a\u304a\u3055\u3089\u3067\u3059\u3002<\/p>\n\n<\/div>\n<\/div>\n<div id=\"faq-5\" class=\"rank-math-list-item\">\n<h3 class=\"rank-math-question\">Resend\u306f\u3069\u306eSMTP\u30ea\u30ec\u30fc\u30b5\u30fc\u30d0\u30fc\u3001\u30dd\u30fc\u30c8\u3001\u30ed\u30b0\u30a4\u30f3\u60c5\u5831\u3092\u4f7f\u7528\u3057\u307e\u3059\u304b\uff1f<\/h3>\n<div class=\"rank-math-answer\">\n\n<p>\u30b5\u30fc\u30d0\u30fc\u306fsmtp.resend.com\u3067\u3059\u3002\u30dd\u30fc\u30c8587\uff08STARTTLS\u5bfe\u5fdc\uff09\u306fMailPlus\u30b5\u30fc\u30d0\u30fc\u3068\u9023\u643a\u3057\u3001\u30dd\u30fc\u30c8465\u306f\u6697\u9ed9\u7684TLS\u306b\u5bfe\u5fdc\u3057\u3066\u3044\u307e\u3059\u3002\u30a2\u30ab\u30a6\u30f3\u30c8\u540d\u306f\u5e38\u306bresend\u3067\u3001\u30d1\u30b9\u30ef\u30fc\u30c9\u306fAPI\u30ad\u30fc\u3067\u3059\u3002<\/p>\n\n<\/div>\n<\/div>\n<div id=\"faq-6\" class=\"rank-math-list-item\">\n<h3 class=\"rank-math-question\">\u65e2\u5b58\u306eSPF\u30ec\u30b3\u30fc\u30c9\u3084DKIM\u30ec\u30b3\u30fc\u30c9\u3092\u5909\u66f4\u3059\u308b\u5fc5\u8981\u306f\u3042\u308a\u307e\u3059\u304b\uff1f<\/h3>\n<div class=\"rank-math-answer\">\n\n<p>\u3044\u3044\u3048\u3002Resend\u306f\u72ec\u81ea\u306e\u30bb\u30ec\u30af\u30bf\u306e\u4e0b\u306bDKIM\u30ad\u30fc\u3092\u8ffd\u52a0\u3057\u3001\u30d0\u30a6\u30f3\u30b9\u30e1\u30fc\u30eb\u306b\u306f\u72ec\u81ea\u306e\u30b5\u30d6\u30c9\u30e1\u30a4\u30f3\u3092\u4f7f\u7528\u3057\u307e\u3059\u3002\u30e1\u30fc\u30eb\u30b5\u30fc\u30d0\u30fc\u304c\u65e2\u306b\u4f7f\u7528\u3057\u3066\u3044\u308b\u30ec\u30b3\u30fc\u30c9\u306f\u305d\u306e\u307e\u307e\u6b8b\u308b\u305f\u3081\u3001\u30c7\u30d5\u30a9\u30eb\u30c8\u30eb\u30fc\u30c8\u3068SMTP\u30ea\u30ec\u30fc\u306e\u4e21\u65b9\u304c\u8a8d\u8a3c\u3055\u308c\u305f\u72b6\u614b\u3092\u7dad\u6301\u3057\u307e\u3059\u3002<\/p>\n\n<\/div>\n<\/div>\n<div id=\"faq-7\" class=\"rank-math-list-item\">\n<h3 class=\"rank-math-question\">\u9867\u5ba2\u306f\u5f15\u304d\u7d9a\u304d\u3001\u9001\u4fe1\u8005\u3068\u3057\u3066\u79c1\u306e\u4f4f\u6240\u3092\u898b\u308b\u3053\u3068\u306b\u306a\u308b\u306e\u3067\u3057\u3087\u3046\u304b\uff1f<\/h3>\n<div class=\"rank-math-answer\">\n\n<p>\u306f\u3044\u3002\u9001\u4fe1\u5143\u30a2\u30c9\u30ec\u30b9\u306f\u5909\u66f4\u3055\u308c\u3066\u304a\u3089\u305a\u3001\u30e1\u30c3\u30bb\u30fc\u30b8\u306f\u304a\u5ba2\u69d8\u306e\u30c9\u30e1\u30a4\u30f3\u3067\u7f72\u540d\u3055\u308c\u3066\u3044\u308b\u305f\u3081\u3001DMARC\u306f\u5408\u683c\u3067\u3059\u3002\u5f0a\u793e\u306e\u30c6\u30b9\u30c8\u3067\u306f\u3001\u76ee\u306b\u898b\u3048\u308b\u5909\u66f4\u306fTo\u3001Message-ID\u3001Date\u3001Received\u30d8\u30c3\u30c0\u30fc\u306b\u9650\u3089\u308c\u3066\u3044\u307e\u3057\u305f\u3002<\/p>\n\n<\/div>\n<\/div>\n<div id=\"faq-8\" class=\"rank-math-list-item\">\n<h3 class=\"rank-math-question\">SMTP\u30ea\u30ec\u30fc\u3092\u3001\u53d7\u4fe1\u8005\u3067\u306f\u306a\u304f\u9001\u4fe1\u8005\u3067\u9078\u629e\u3059\u308b\u3053\u3068\u306f\u3067\u304d\u307e\u3059\u304b\uff1f<\/h3>\n<div class=\"rank-math-answer\">\n\n<p>MailPlus\u30b5\u30fc\u30d0\u30fc\u306b\u306f\u3001\u53d7\u4fe1\u8005\u30eb\u30fc\u30eb\u306e\u6a2a\u306b\u3001\u9001\u4fe1\u30a2\u30c9\u30ec\u30b9\u306b\u3088\u308b\u30eb\u30fc\u30c6\u30a3\u30f3\u30b0\u3092\u884c\u3046\u305f\u3081\u306e\u9001\u4fe1\u8005\u30eb\u30fc\u30eb\u30bf\u30d6\u304c\u3042\u308a\u307e\u3059\u3002\u4e21\u65b9\u306e\u30eb\u30fc\u30eb\u304c\u540c\u3058\u30e1\u30c3\u30bb\u30fc\u30b8\u306b\u4e00\u81f4\u3059\u308b\u5834\u5408\u3001\u30b3\u30f3\u30bd\u30fc\u30eb\u306b\u306f\u53d7\u4fe1\u8005\u30eb\u30fc\u30eb\u304c\u512a\u5148\u3055\u308c\u308b\u3053\u3068\u304c\u8868\u793a\u3055\u308c\u307e\u3059\u3002<\/p>\n\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n\n\n<h2 id=\"references-and-video-walkthroughs\" class=\"wp-block-heading\">\u53c2\u8003\u8cc7\u6599\u3068\u30d3\u30c7\u30aa\u30c1\u30e5\u30fc\u30c8\u30ea\u30a2\u30eb<\/h2>\n\n\n\n<ul class=\"wp-block-list\">\n<li><a href=\"https:\/\/resend.com\/docs\/send-with-smtp\" target=\"_blank\" rel=\"noreferrer noopener nofollow\">SMTP\u30c9\u30ad\u30e5\u30e1\u30f3\u30c8\u3092\u518d\u9001\u4fe1<\/a>\u30b5\u30fc\u30d0\u30fc\u540d\u3001\u5229\u7528\u53ef\u80fd\u306a\u30dd\u30fc\u30c8\u3001\u30ed\u30b0\u30a4\u30f3\u5f62\u5f0f\u3092\u4e00\u89a7\u8868\u793a\u3057\u307e\u3059\u3002<\/li>\n\n\n\n<li><a href=\"https:\/\/resend.com\/pricing\" target=\"_blank\" rel=\"noreferrer noopener nofollow\">\u518d\u9001\u4fe1\u6599\u91d1<\/a>\u7121\u6599\u30d7\u30e9\u30f3\u3068\u6709\u6599\u30d7\u30e9\u30f3\u306e\u73fe\u5728\u306e\u5229\u7528\u5236\u9650\u306b\u3064\u3044\u3066\u3002<\/li>\n\n\n\n<li><a href=\"https:\/\/kb.synology.com\/en-global\/DSM\/help\/MailPlus-Server\/mailplus_server_delivery\" target=\"_blank\" rel=\"noreferrer noopener\">Synology MailPlus\u30b5\u30fc\u30d0\u30fc\u30e1\u30fc\u30eb\u914d\u4fe1\u30d8\u30eb\u30d7<\/a>\u914d\u9001\u304a\u3088\u3073\u4e2d\u7d99\u8a2d\u5b9a\u306e\u516c\u5f0f\u8aac\u660e\u3002<\/li>\n\n\n\n<li><a href=\"https:\/\/support.google.com\/a\/answer\/81126\" target=\"_blank\" rel=\"noreferrer noopener nofollow\">Google\u306e\u30e1\u30fc\u30eb\u9001\u4fe1\u8005\u5411\u3051\u30ac\u30a4\u30c9\u30e9\u30a4\u30f3<\/a>\u3053\u308c\u306f\u3001Gmail\u304c\u53d7\u4fe1\u30e1\u30fc\u30eb\u306b\u9069\u7528\u3059\u308b\u8a8d\u8a3c\u304a\u3088\u3073\u8a55\u5224\u306b\u95a2\u3059\u308b\u30eb\u30fc\u30eb\u3067\u3059\u3002<\/li>\n\n\n\n<li><a href=\"https:\/\/dmarc.org\/overview\/\" target=\"_blank\" rel=\"noreferrer noopener nofollow\">DMARC\u306e\u6982\u8981<\/a>SPF\u3068DKIM\u306e\u9023\u643a\u306b\u3088\u3063\u3066\u30e1\u30c3\u30bb\u30fc\u30b8\u304c\u901a\u904e\u3059\u308b\u304b\u3069\u3046\u304b\u304c\u3069\u306e\u3088\u3046\u306b\u6c7a\u5b9a\u3055\u308c\u308b\u304b\u3092\u8aac\u660e\u3057\u307e\u3059\u3002<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">\u3053\u308c\u3089\u306eSynology\u306e\u52d5\u753b\u3067\u306f\u3001\u3053\u306e\u8a18\u4e8b\u306e\u57fa\u306b\u306a\u3063\u3066\u3044\u308b\u30e1\u30fc\u30eb\u30b5\u30fc\u30d0\u30fc\u306b\u3064\u3044\u3066\u3001\u6700\u521d\u306e\u30a4\u30f3\u30b9\u30c8\u30fc\u30eb\u304b\u3089\u30bb\u30ad\u30e5\u30ea\u30c6\u30a3\u8a2d\u5b9a\u307e\u3067\u3092\u89e3\u8aac\u3057\u3066\u3044\u307e\u3059\u3002<\/p>\n\n\n\n<figure class=\"wp-block-embed is-type-video is-provider-youtube wp-block-embed-youtube wp-embed-aspect-16-9 wp-has-aspect-ratio\"><div class=\"wp-block-embed__wrapper\">\n<iframe title=\"Synology MailPlus \u30b5\u30fc\u30d0\u30fc\u306e\u8a2d\u5b9a\u65b9\u6cd5\" width=\"1200\" height=\"675\" src=\"https:\/\/www.youtube.com\/embed\/tBLjJWn-WBk?feature=oembed\" frameborder=\"0\" allow=\"accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture; web-share\" referrerpolicy=\"strict-origin-when-cross-origin\" allowfullscreen><\/iframe>\n<\/div><figcaption class=\"wp-element-caption\">Synology MailPlus \u30b5\u30fc\u30d0\u30fc\u306e\u8a2d\u5b9a\u65b9\u6cd5<\/figcaption><\/figure>\n\n\n\n<figure class=\"wp-block-embed is-type-video is-provider-youtube wp-block-embed-youtube wp-embed-aspect-16-9 wp-has-aspect-ratio\"><div class=\"wp-block-embed__wrapper\">\n<iframe title=\"\u30e1\u30fc\u30eb\u30b5\u30fc\u30d3\u30b9\u3092\u4fdd\u8b77\u3059\u308b\u305f\u3081\u306bSynology MailPlus\u30b5\u30fc\u30d0\u30fc\u3092\u8a2d\u5b9a\u3059\u308b\u65b9\u6cd5\" width=\"1200\" height=\"675\" src=\"https:\/\/www.youtube.com\/embed\/I_ap-K0Y9jg?feature=oembed\" frameborder=\"0\" allow=\"accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture; web-share\" referrerpolicy=\"strict-origin-when-cross-origin\" allowfullscreen><\/iframe>\n<\/div><figcaption class=\"wp-element-caption\">\u30e1\u30fc\u30eb\u30b5\u30fc\u30d3\u30b9\u3092\u4fdd\u8b77\u3059\u308b\u305f\u3081\u306bSynology MailPlus\u30b5\u30fc\u30d0\u30fc\u3092\u8a2d\u5b9a\u3059\u308b\u65b9\u6cd5<\/figcaption><\/figure>\n\n\n\n<figure class=\"wp-block-embed is-type-video is-provider-youtube wp-block-embed-youtube wp-embed-aspect-16-9 wp-has-aspect-ratio\"><div class=\"wp-block-embed__wrapper\">\n<iframe title=\"Synology MailPlus | Synology \u3092\u3054\u7d39\u4ecb\u3057\u307e\u3059\" width=\"1200\" height=\"675\" src=\"https:\/\/www.youtube.com\/embed\/3XGTSb3D3TA?feature=oembed\" frameborder=\"0\" allow=\"accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture; web-share\" referrerpolicy=\"strict-origin-when-cross-origin\" allowfullscreen><\/iframe>\n<\/div><figcaption class=\"wp-element-caption\">Synology MailPlus\u306e\u3054\u7d39\u4ecb<\/figcaption><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">NAS\u4e0a\u3067\u30d3\u30b8\u30cd\u30b9\u3092\u30db\u30b9\u30c6\u30a3\u30f3\u30b0\u3059\u308b\u65b9\u6cd5\u306b\u95a2\u3059\u308b\u3053\u306e\u30b7\u30ea\u30fc\u30ba\u306e\u305d\u306e\u4ed6\u306e\u8a18\u4e8b\uff1a <a href=\"\/ja\/docs\/email-bombing-contact-form-synology-nas\/\">\u554f\u3044\u5408\u308f\u305b\u30d5\u30a9\u30fc\u30e0\u3092\u901a\u3058\u305f\u30e1\u30fc\u30eb\u7206\u6483<\/a>\u72ec\u81ea\u306e\u30e1\u30fc\u30eb\u30b5\u30fc\u30d0\u30fc\u3092\u8a08\u753b\u3057\u3066\u3044\u307e\u3059\u304b\uff1f\u307e\u305a\u306f <a href=\"https:\/\/synopower.club\/ja\/synology-mailplus-5%e3%82%a2%e3%82%ab%e3%82%a6%e3%83%b3%e3%83%88\/\" target=\"_blank\" rel=\"noreferrer noopener\">MailPlus\u30e9\u30a4\u30bb\u30f3\u30b9\u30d1\u30c3\u30af<\/a>\u307e\u305f\u306f\u3001\u3059\u3079\u3066\u306e\u30e9\u30a4\u30bb\u30f3\u30b9\u3092\u95b2\u89a7\u3059\u308b\u306b\u306f <a href=\"https:\/\/synopower.club\/ja\/\" target=\"_blank\" rel=\"noreferrer noopener\">SynoPower Club<\/a>.<\/p>","protected":false},"excerpt":{"rendered":"<p>An SMTP relay is a second mail server that sends your messages on your behalf, so the receiving side judges its reputation instead of yours. On 9 October 2026 we needed one in a hurry. SynoPower Club runs entirely on Synology, and every order confirmation and license key leaves through Synology MailPlus. That evening a customer in Belgium paid for a license, and the email carrying the key came straight back with 552 5.2.0 Your message is considered spam. SPF, DKIM and DMARC were all passing. This NAS Hosting 101 article shows how we added Resend as an SMTP relay for only the recipient domains that reject us, which records [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":21887,"comment_status":"open","ping_status":"closed","template":"","meta":{"_eb_attr":"","footnotes":""},"doc_category":[197],"doc_tag":[],"class_list":["post-21891","docs","type-docs","status-publish","has-post-thumbnail","hentry","doc_category-nas-hosting-101"],"blocksy_meta":{"styles_descriptor":{"styles":{"desktop":"","tablet":"","mobile":""},"google_fonts":[],"version":8}},"year_month":"2026-10","word_count":2919,"total_views":"7","reactions":{"happy":"0","normal":"0","sad":"0"},"author_info":{"name":"\u30a2\u30c7\u30a2\u30fb\u30b9\u30fc","author_nicename":"adairpk17","author_url":"https:\/\/synopower.club\/ja\/author\/adairpk17\/"},"doc_category_info":[{"term_name":"NAS Hosting 101","term_url":"https:\/\/synopower.club\/ja\/docs-category\/nas-hosting-101\/"}],"doc_tag_info":[],"_links":{"self":[{"href":"https:\/\/synopower.club\/ja\/wp-json\/wp\/v2\/docs\/21891","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/synopower.club\/ja\/wp-json\/wp\/v2\/docs"}],"about":[{"href":"https:\/\/synopower.club\/ja\/wp-json\/wp\/v2\/types\/docs"}],"author":[{"embeddable":true,"href":"https:\/\/synopower.club\/ja\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/synopower.club\/ja\/wp-json\/wp\/v2\/comments?post=21891"}],"version-history":[{"count":2,"href":"https:\/\/synopower.club\/ja\/wp-json\/wp\/v2\/docs\/21891\/revisions"}],"predecessor-version":[{"id":21897,"href":"https:\/\/synopower.club\/ja\/wp-json\/wp\/v2\/docs\/21891\/revisions\/21897"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/synopower.club\/ja\/wp-json\/wp\/v2\/media\/21887"}],"wp:attachment":[{"href":"https:\/\/synopower.club\/ja\/wp-json\/wp\/v2\/media?parent=21891"}],"wp:term":[{"taxonomy":"doc_category","embeddable":true,"href":"https:\/\/synopower.club\/ja\/wp-json\/wp\/v2\/doc_category?post=21891"},{"taxonomy":"doc_tag","embeddable":true,"href":"https:\/\/synopower.club\/ja\/wp-json\/wp\/v2\/doc_tag?post=21891"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}