{"id":5782,"date":"2022-01-24T07:56:44","date_gmt":"2022-01-24T13:56:44","guid":{"rendered":"https:\/\/www.knownhost.com\/kb\/?p=5782"},"modified":"2022-08-23T12:59:43","modified_gmt":"2022-08-23T17:59:43","slug":"smtp-error-551","status":"publish","type":"post","link":"https:\/\/www.knownhost.com\/kb\/smtp-error-551\/","title":{"rendered":"SMTP Error 551"},"content":{"rendered":"<div id=\"ez-toc-container\" class=\"ez-toc-v2_0_82_2 ez-toc-wrap-right counter-hierarchy ez-toc-counter ez-toc-custom ez-toc-container-direction\">\n<div class=\"ez-toc-title-container\">\n<p class=\"ez-toc-title\" style=\"cursor:inherit\">Table of Contents<\/p>\n<span class=\"ez-toc-title-toggle\"><a href=\"#\" class=\"ez-toc-pull-right ez-toc-btn ez-toc-btn-xs ez-toc-btn-default ez-toc-toggle\" aria-label=\"Toggle Table of Content\"><span class=\"ez-toc-js-icon-con\"><span class=\"\"><span class=\"eztoc-hide\" style=\"display:none;\">Toggle<\/span><span class=\"ez-toc-icon-toggle-span\"><svg style=\"fill: #212121;color:#212121\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" class=\"list-377408\" width=\"20px\" height=\"20px\" viewBox=\"0 0 24 24\" fill=\"none\"><path d=\"M6 6H4v2h2V6zm14 0H8v2h12V6zM4 11h2v2H4v-2zm16 0H8v2h12v-2zM4 16h2v2H4v-2zm16 0H8v2h12v-2z\" fill=\"currentColor\"><\/path><\/svg><svg style=\"fill: #212121;color:#212121\" class=\"arrow-unsorted-368013\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" width=\"10px\" height=\"10px\" viewBox=\"0 0 24 24\" version=\"1.2\" baseProfile=\"tiny\"><path d=\"M18.2 9.3l-6.2-6.3-6.2 6.3c-.2.2-.3.4-.3.7s.1.5.3.7c.2.2.4.3.7.3h11c.3 0 .5-.1.7-.3.2-.2.3-.5.3-.7s-.1-.5-.3-.7zM5.8 14.7l6.2 6.3 6.2-6.3c.2-.2.3-.5.3-.7s-.1-.5-.3-.7c-.2-.2-.4-.3-.7-.3h-11c-.3 0-.5.1-.7.3-.2.2-.3.5-.3.7s.1.5.3.7z\"\/><\/svg><\/span><\/span><\/span><\/a><\/span><\/div>\n<nav><ul class='ez-toc-list ez-toc-list-level-1 eztoc-toggle-hide-by-default' ><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-1\" href=\"https:\/\/www.knownhost.com\/kb\/smtp-error-551\/#what_does_this_mean\" >What does this mean?<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-2\" href=\"https:\/\/www.knownhost.com\/kb\/smtp-error-551\/#how_to_fix_smtp_error_551\" >How to fix SMTP Error 551?<\/a><\/li><\/ul><\/nav><\/div>\n\n<p><strong>Description<\/strong>: User not local; please try &lt;FORWARD PATH&gt;.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"what_does_this_mean\"><\/span>What does this mean?<span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<p>This is commonly used as a strategy for spam prevention. It&#8217;s stating that mail relaying is not allowed for some reason. It may be due to the email address or authentication settings used.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"how_to_fix_smtp_error_551\"><span class=\"ez-toc-section\" id=\"how_to_fix_smtp_error_551\"><\/span>How to fix SMTP Error 551?<span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<ul class=\"wp-block-list\"><li>Ensure proper email authentication.<\/li><li>Allow SMTP relays (if you are certain you want that.)<\/li><\/ul>\n","protected":false},"excerpt":{"rendered":"<p>Description: User not local; please try &lt;FORWARD PATH&gt;. What does this mean? This is commonly used as a strategy for spam prevention. It&#8217;s stating that mail relaying is not allowed for some reason. It may be due to the email address or authentication settings used. How to fix SMTP Error 551? Ensure proper email authentication. [&hellip;]<\/p>\n","protected":false},"author":6,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[97],"tags":[581,380,291],"class_list":["post-5782","post","type-post","status-publish","format-standard","hentry","category-other","tag-581","tag-error","tag-smtp"],"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v27.5 - https:\/\/yoast.com\/product\/yoast-seo-wordpress\/ -->\n<title>SMTP Error 551 - KnownHost<\/title>\n<meta name=\"description\" content=\"KnownHost self-hosted email guide to help you troubleshoot and fix SMTP Error 551 on your premium KnownHost server.\" \/>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/www.knownhost.com\/kb\/smtp-error-551\/\" \/>\n<meta property=\"og:locale\" content=\"en_US\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"SMTP Error 551 - 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