{"id":26034,"date":"2025-09-15T12:02:27","date_gmt":"2025-09-15T10:02:27","guid":{"rendered":"https:\/\/contabo.com\/blog\/?p=26034"},"modified":"2026-01-16T12:48:31","modified_gmt":"2026-01-16T11:48:31","slug":"why-arent-my-emails-delivered","status":"publish","type":"post","link":"https:\/\/contabo.com\/blog\/why-arent-my-emails-delivered\/","title":{"rendered":"Why Aren\u2019t My Emails Delivered?"},"content":{"rendered":"\n<p>If your emails fail to reach recipients, your configuration may be incorrect or flagged as spam. Common issues involve missing or incorrect SPF, DKIM, DMARC, or Reverse DNS (PTR) records. This guide explains how to fix these problems and improve email deliverability.&nbsp;<\/p>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"h-reverse-dns-check-setting-up-a-ptr-record\">Reverse DNS Check &#8211; Setting Up a PTR Record\u00a0<\/h2>\n\n\n\n<p>A <strong>PTR record<\/strong> (Reverse DNS) links your server\u2019s IP address back to your domain. This proves your legitimacy to email providers. Without it, emails might be rejected.&nbsp;<\/p>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"h-how-to-set-it-up\">How to set it up:\u00a0<\/h3>\n\n\n\n<ol start=\"1\" class=\"wp-block-list\">\n<li>Log in to your hosting provider\u2019s DNS settings.&nbsp;<\/li>\n<\/ol>\n\n\n\n<ol start=\"2\" class=\"wp-block-list\">\n<li>Add a PTR record for your server\u2019s IP address.&nbsp;<\/li>\n<\/ol>\n\n\n\n<p><strong>Contabo customers:<\/strong> Use the <a href=\"https:\/\/my.contabo.com\/\" target=\"_blank\" rel=\"noreferrer noopener\"><strong>Customer Control Panel<\/strong><\/a><strong> \u2192 Reverse DNS Management<\/strong> to configure PTR records easily.&nbsp;<\/p>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"h-spf-record-preventing-spoofing\">SPF Record &#8211; Preventing Spoofing\u00a0<\/h2>\n\n\n\n<p><strong>SPF (Sender Policy Framework)<\/strong> lets you authorize which mail servers can send emails on behalf of your domain. Without SPF, email servers may treat your messages as fake. SPF ensures that mail servers can verify that your messages are legitimate.&nbsp;<\/p>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"h-to-configure-spf\">To configure SPF:\u00a0<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Add a TXT record to your DNS like this:&nbsp;<\/li>\n<\/ul>\n\n\n\n<pre class=\"wp-block-code\"><code>v=spf1 +a +mx ~all&nbsp;<\/code><\/pre>\n\n\n\n<ul class=\"wp-block-list\">\n<li>If you use an external mail relay, include it with <code>include:<\/code>. (Domain names should always be blurred in screenshots or examples.)&nbsp;<\/li>\n<\/ul>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"h-dkim-amp-dmarc-email-authentication-amp-protection\">DKIM &amp; DMARC &#8211; Email Authentication &amp; Protection\u00a0<\/h2>\n\n\n\n<p><strong>DKIM (DomainKeys Identified Mail)<\/strong> adds a digital signature to emails, ensuring they haven\u2019t been altered during transit.&nbsp;<\/p>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"h-to-enable-dkim\">To enable DKIM:\u00a0<\/h3>\n\n\n\n<ol start=\"1\" class=\"wp-block-list\">\n<li>Generate a DKIM key in your mail server settings.&nbsp;<\/li>\n<\/ol>\n\n\n\n<ol start=\"2\" class=\"wp-block-list\">\n<li>Add a TXT record to your DNS:&nbsp;<\/li>\n<\/ol>\n\n\n\n<pre class=\"wp-block-code\"><code>v=DKIM1; p=...&nbsp;<\/code><\/pre>\n\n\n\n<p><strong>DMARC<\/strong> tells email providers how to handle messages that fail SPF or DKIM checks and provides reporting:&nbsp;<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>v=DMARC1; p=reject; rua=mailto:admin@example.com&nbsp;<\/code><\/pre>\n\n\n\n<p>DMARC reports let you monitor unauthorized email activity.&nbsp;<\/p>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"h-watch-our-youtube-video-to-fix-email-delivery-issues\">Watch Our YouTube Video  to fix email delivery issues<\/h2>\n\n\n\n<p>If you prefer a visual walk-through, we have a YouTube video on our channel ready for you:&nbsp;<\/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<div class=\"ast-oembed-container \" style=\"height: 100%;\"><iframe loading=\"lazy\" title=\"Why aren&#039;t my emails delivered?\" width=\"500\" height=\"281\" src=\"https:\/\/www.youtube.com\/embed\/khGCaGhTGy8?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><\/div>\n<\/div><\/figure>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"h-conclusion\">Conclusion\u00a0<\/h2>\n\n\n\n<p>After configuring PTR, SPF, DKIM, and DMARC, test your setup using tools such as <strong>MX Toolbox<\/strong>, <strong>Mail-Tester<\/strong>, or <strong>DMARC Analyzer<\/strong>:&nbsp;<\/p>\n\n\n\n<p>Check SPF, DKIM, DMARC at mxtoolbox.com&nbsp;<\/p>\n\n\n\n<p>Following these steps delivers your emails reliably and securely.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>If your emails fail to reach recipients, your configuration may be incorrect or flagged as spam. Common issues involve missing or incorrect SPF, DKIM, DMARC, or Reverse DNS (PTR) records. This guide explains how to fix these problems and improve email deliverability.&nbsp; Reverse DNS Check &#8211; Setting Up a PTR Record\u00a0 A PTR record (Reverse [&hellip;]<\/p>\n","protected":false},"author":77,"featured_media":26038,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"inline_featured_image":false,"_uag_custom_page_level_css":"","site-sidebar-layout":"default","site-content-layout":"","ast-site-content-layout":"default","site-content-style":"default","site-sidebar-style":"default","ast-global-header-display":"","ast-banner-title-visibility":"","ast-main-header-display":"","ast-hfb-above-header-display":"","ast-hfb-below-header-display":"","ast-hfb-mobile-header-display":"","site-post-title":"","ast-breadcrumbs-content":"","ast-featured-img":"","footer-sml-layout":"","theme-transparent-header-meta":"","adv-header-id-meta":"","stick-header-meta":"","header-above-stick-meta":"","header-main-stick-meta":"","header-below-stick-meta":"","astra-migrate-meta-layouts":"set","ast-page-background-enabled":"default","ast-page-background-meta":{"desktop":{"background-color":"var(--ast-global-color-4)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"ast-content-background-meta":{"desktop":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"footnotes":""},"categories":[18],"tags":[],"ppma_author":[3116],"class_list":["post-26034","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-tutorials"],"uagb_featured_image_src":{"full":["https:\/\/contabo.com\/blog\/wp-content\/uploads\/2025\/11\/Emal.png",1200,630,false],"thumbnail":["https:\/\/contabo.com\/blog\/wp-content\/uploads\/2025\/11\/Emal-150x150.png",150,150,true],"medium":["https:\/\/contabo.com\/blog\/wp-content\/uploads\/2025\/11\/Emal-600x315.png",600,315,true],"medium_large":["https:\/\/contabo.com\/blog\/wp-content\/uploads\/2025\/11\/Emal-768x403.png",768,403,true],"large":["https:\/\/contabo.com\/blog\/wp-content\/uploads\/2025\/11\/Emal.png",1200,630,false],"1536x1536":["https:\/\/contabo.com\/blog\/wp-content\/uploads\/2025\/11\/Emal.png",1200,630,false],"2048x2048":["https:\/\/contabo.com\/blog\/wp-content\/uploads\/2025\/11\/Emal.png",1200,630,false]},"uagb_author_info":{"display_name":"Anika Kopte","author_link":"https:\/\/contabo.com\/blog\/author\/anika\/"},"uagb_comment_info":0,"uagb_excerpt":"If your emails fail to reach recipients, your configuration may be incorrect or flagged as spam. Common issues involve missing or incorrect SPF, DKIM, DMARC, or Reverse DNS (PTR) records. This guide explains how to fix these problems and improve email deliverability.&nbsp; Reverse DNS Check &#8211; Setting Up a PTR Record\u00a0 A PTR record (Reverse&hellip;","authors":[{"term_id":3116,"user_id":77,"is_guest":0,"slug":"anika","display_name":"Anika Kopte","avatar_url":"https:\/\/secure.gravatar.com\/avatar\/1c425caa652c679ae47e3f85a48de4e19f09d37bcb5593ba88a7aa4a08bb1d81?s=96&d=mm&r=g","0":null,"1":"","2":"","3":"","4":"","5":"","6":"","7":"","8":""}],"_links":{"self":[{"href":"https:\/\/contabo.com\/blog\/wp-json\/wp\/v2\/posts\/26034","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/contabo.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/contabo.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/contabo.com\/blog\/wp-json\/wp\/v2\/users\/77"}],"replies":[{"embeddable":true,"href":"https:\/\/contabo.com\/blog\/wp-json\/wp\/v2\/comments?post=26034"}],"version-history":[{"count":2,"href":"https:\/\/contabo.com\/blog\/wp-json\/wp\/v2\/posts\/26034\/revisions"}],"predecessor-version":[{"id":27399,"href":"https:\/\/contabo.com\/blog\/wp-json\/wp\/v2\/posts\/26034\/revisions\/27399"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/contabo.com\/blog\/wp-json\/wp\/v2\/media\/26038"}],"wp:attachment":[{"href":"https:\/\/contabo.com\/blog\/wp-json\/wp\/v2\/media?parent=26034"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/contabo.com\/blog\/wp-json\/wp\/v2\/categories?post=26034"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/contabo.com\/blog\/wp-json\/wp\/v2\/tags?post=26034"},{"taxonomy":"author","embeddable":true,"href":"https:\/\/contabo.com\/blog\/wp-json\/wp\/v2\/ppma_author?post=26034"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}