{"id":2549,"date":"2026-02-23T12:16:17","date_gmt":"2026-02-23T12:16:17","guid":{"rendered":"https:\/\/cyberpanel.net\/KnowledgeBase\/improving-email-deliverability\/"},"modified":"2026-02-23T12:17:19","modified_gmt":"2026-02-23T12:17:19","slug":"improving-email-deliverability","status":"publish","type":"post","link":"https:\/\/cyberpanel.net\/KnowledgeBase\/improving-email-deliverability\/","title":{"rendered":"Improving Email Deliverability"},"content":{"rendered":"<style>\n.kb-info-box { background: #e8f4fd; border-left: 4px solid #2196F3; padding: 16px 20px; margin: 20px 0; border-radius: 4px; }\n.kb-info-box.warning { background: #fff8e1; border-left-color: #ff9800; }\n.kb-info-box.success { background: #e8f5e9; border-left-color: #4caf50; }\n.kb-info-box.tip { background: #f3e5f5; border-left-color: #9c27b0; }\n.kb-info-box strong { display: block; margin-bottom: 4px; }\n.kb-table { width: 100%; border-collapse: collapse; margin: 20px 0; }\n.kb-table th, .kb-table td { border: 1px solid #ddd; padding: 10px 14px; text-align: left; }\n.kb-table th { background: #f5f5f5; font-weight: 600; }\n.kb-table tr:nth-child(even) { background: #fafafa; }\n.kb-code { background: #1e1e1e; color: #d4d4d4; padding: 16px 20px; border-radius: 6px; overflow-x: auto; margin: 16px 0; font-size: 14px; line-height: 1.5; }\n.kb-code .comment { color: #6a9955; }\n.kb-code .keyword { color: #569cd6; }\n.kb-code .string { color: #ce9178; }\n<\/style>\n<p>Email deliverability is about making sure your emails reach the inbox, not the spam folder. This guide covers the three pillars of deliverability: authentication, reputation, and content.<\/p>\n<h2>Pillar 1: Authentication (SPF, DKIM, DMARC)<\/h2>\n<p>Authentication proves to receiving servers that you&#8217;re authorized to send email for your domain.<\/p>\n<h3>SPF (Sender Policy Framework)<\/h3>\n<p>SPF lists which mail servers can send email on your domain&#8217;s behalf.<\/p>\n<pre class=\"kb-code\"><span class=\"comment\">\/\/ Add this TXT record to your domain's DNS:<\/span>\nv=spf1 include:spf.cyberpersons.com ~all<\/pre>\n<ul>\n<li><code>include:spf.cyberpersons.com<\/code> authorizes all CyberPanel mail servers<\/li>\n<li><code>~all<\/code> tells receivers to soft-fail emails from unauthorized servers<\/li>\n<li><strong>SPF fail<\/strong> adds +5 to CyberMail&#8217;s spam score; <strong>soft-fail<\/strong> adds +2<\/li>\n<\/ul>\n<h3>DKIM (DomainKeys Identified Mail)<\/h3>\n<p>DKIM adds a cryptographic signature to every email, proving it wasn&#8217;t tampered with in transit.<\/p>\n<ul>\n<li>CyberMail automatically signs all outgoing emails with your domain&#8217;s DKIM key<\/li>\n<li>The public key is published as a TXT record at <code>postal._domainkey.yourdomain.com<\/code> (sending) or <code>mail._domainkey.yourdomain.com<\/code> (hosting)<\/li>\n<li>Keys are 2048-bit RSA, generated automatically when you add a domain<\/li>\n<\/ul>\n<h3>DMARC (Domain-based Message Authentication)<\/h3>\n<p>DMARC tells receiving servers what to do when SPF or DKIM fail.<\/p>\n<pre class=\"kb-code\"><span class=\"comment\">\/\/ Recommended DMARC record:<\/span>\nv=DMARC1; p=quarantine; rua=mailto:dmarc@yourdomain.com<\/pre>\n<ul>\n<li><code>p=quarantine<\/code> &mdash; Failed emails are sent to spam (start here)<\/li>\n<li><code>p=reject<\/code> &mdash; Failed emails are rejected entirely (move to this after confirming everything works)<\/li>\n<li><code>rua=mailto:<\/code> &mdash; Receive aggregate reports about authentication results<\/li>\n<\/ul>\n<p>See <a href=\"https:\/\/cyberpanel.net\/KnowledgeBase\/domain-verification-dns-setup\/\">Domain Verification &amp; DNS Setup<\/a> for step-by-step DNS configuration.<\/p>\n<h2>Pillar 2: Reputation<\/h2>\n<p>Your domain and account reputation directly affect inbox placement.<\/p>\n<h3>Domain Reputation Scoring<\/h3>\n<p>CyberPanel tracks your domain reputation on a 0&ndash;100 scale:<\/p>\n<table class=\"kb-table\">\n<tr>\n<th>Event<\/th>\n<th>Impact<\/th>\n<\/tr>\n<tr>\n<td>Successful delivery<\/td>\n<td>+0.1<\/td>\n<\/tr>\n<tr>\n<td>Hard bounce<\/td>\n<td>-2<\/td>\n<\/tr>\n<tr>\n<td>Spam complaint<\/td>\n<td>-5<\/td>\n<\/tr>\n<tr>\n<td>Bounce rate &gt; 5%<\/td>\n<td>-30 penalty<\/td>\n<\/tr>\n<tr>\n<td>Complaint rate &gt; 0.1%<\/td>\n<td>-50 penalty<\/td>\n<\/tr>\n<\/table>\n<h3>How to Maintain Good Reputation<\/h3>\n<ul>\n<li><strong>Clean your lists:<\/strong> Remove invalid addresses and unengaged subscribers regularly<\/li>\n<li><strong>Use double opt-in:<\/strong> Require email confirmation for new subscribers<\/li>\n<li><strong>Honor unsubscribes:<\/strong> Process unsubscribe requests immediately<\/li>\n<li><strong>Monitor bounces:<\/strong> Remove hard-bounced addresses from your list<\/li>\n<li><strong>Warm up gradually:<\/strong> When starting, send to small batches and increase volume over days<\/li>\n<\/ul>\n<h2>Pillar 3: Content<\/h2>\n<p>Even with perfect authentication and reputation, poor content can trigger spam filters.<\/p>\n<h3>Best Practices<\/h3>\n<ul>\n<li>Avoid spam trigger words in subject lines (&#8220;FREE!!!&#8221;, &#8220;Act now!!!&#8221;, all-caps)<\/li>\n<li>Maintain a good text-to-image ratio (don&#8217;t send image-only emails)<\/li>\n<li>Include a plain-text version alongside HTML<\/li>\n<li>Use a consistent From name and address<\/li>\n<li>Include a physical mailing address (required by CAN-SPAM)<\/li>\n<li>Always include an unsubscribe link in marketing emails<\/li>\n<\/ul>\n<h2>CyberMail Anti-Spam Protection<\/h2>\n<p>CyberMail includes built-in anti-spam that scans both incoming and outgoing email:<\/p>\n<ul>\n<li><strong>DNSBL checking:<\/strong> Queries Spamhaus DBL, SURBL, and Barracuda blocklists<\/li>\n<li><strong>URL scanning:<\/strong> Checks links against blocklists, detects suspicious TLDs and IP-based URLs<\/li>\n<li><strong>SPF verification:<\/strong> Validates sender authorization<\/li>\n<li><strong>Content scoring:<\/strong> Assigns a spam score; emails above the threshold are flagged or rejected<\/li>\n<\/ul>\n<h2>Multi-Node Failover<\/h2>\n<p>CyberPanel Email runs on 4 geographically distributed nodes. If one node is down or busy, your email automatically routes through another node &mdash; ensuring 99.9% uptime.<\/p>\n<h2>Deliverability Checklist<\/h2>\n<div class=\"kb-info-box success\"><strong>Pre-launch checklist:<\/strong><\/p>\n<ul style=\"margin:8px 0 0 0\">\n<li>SPF record includes <code>include:spf.cyberpersons.com<\/code><\/li>\n<li>DKIM record published and verified in dashboard<\/li>\n<li>DMARC record set to at least <code>p=quarantine<\/code><\/li>\n<li>Domain verified and showing green checkmarks<\/li>\n<li>Mailing list is opt-in and recently cleaned<\/li>\n<li>Unsubscribe link included in all marketing emails<\/li>\n<li>Test email sent and landing in inbox (not spam)<\/li>\n<\/ul>\n<\/div>\n<h2>Related Guides<\/h2>\n<ul>\n<li><a href=\"https:\/\/cyberpanel.net\/KnowledgeBase\/email-service-documentation\/\">Documentation Hub<\/a><\/li>\n<li><a href=\"https:\/\/cyberpanel.net\/KnowledgeBase\/getting-started-email-delivery\/\">Getting Started with Email Delivery<\/a><\/li>\n<li><a href=\"https:\/\/cyberpanel.net\/KnowledgeBase\/domain-verification-dns-setup\/\">Domain Verification &amp; DNS Setup<\/a><\/li>\n<li><a href=\"https:\/\/cyberpanel.net\/KnowledgeBase\/email-analytics-and-logs\/\">Email Analytics and Logs<\/a><\/li>\n<li><a href=\"https:\/\/cyberpanel.net\/KnowledgeBase\/plans-pricing-rate-limits\/\">Plans, Pricing, and Rate Limits<\/a><\/li>\n<\/ul>\n<p><a href=\"https:\/\/cyberpanel.net\/KnowledgeBase\/email-service-documentation\/\">&larr; Back to Documentation Hub<\/a><\/p>\n","protected":false},"excerpt":{"rendered":"<p>Email deliverability is about making sure your emails reach the inbox, not the spam folder. This guide covers the three pillars of deliverability: authentication, reputation, and content. Pillar 1: Authentication (SPF, DKIM, DMARC) Authentication proves to receiving servers that you&#8217;re authorized to send email for your domain. SPF (Sender Policy Framework) SPF lists which mail [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[108],"tags":[],"class_list":["post-2549","post","type-post","status-publish","format-standard","hentry","category-email-service"],"_links":{"self":[{"href":"https:\/\/cyberpanel.net\/KnowledgeBase\/wp-json\/wp\/v2\/posts\/2549","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/cyberpanel.net\/KnowledgeBase\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/cyberpanel.net\/KnowledgeBase\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/cyberpanel.net\/KnowledgeBase\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/cyberpanel.net\/KnowledgeBase\/wp-json\/wp\/v2\/comments?post=2549"}],"version-history":[{"count":3,"href":"https:\/\/cyberpanel.net\/KnowledgeBase\/wp-json\/wp\/v2\/posts\/2549\/revisions"}],"predecessor-version":[{"id":2591,"href":"https:\/\/cyberpanel.net\/KnowledgeBase\/wp-json\/wp\/v2\/posts\/2549\/revisions\/2591"}],"wp:attachment":[{"href":"https:\/\/cyberpanel.net\/KnowledgeBase\/wp-json\/wp\/v2\/media?parent=2549"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/cyberpanel.net\/KnowledgeBase\/wp-json\/wp\/v2\/categories?post=2549"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/cyberpanel.net\/KnowledgeBase\/wp-json\/wp\/v2\/tags?post=2549"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}