{"id":34672,"date":"2026-06-09T09:20:15","date_gmt":"2026-06-09T09:20:15","guid":{"rendered":"https:\/\/1grid.co.za\/knowledge\/?post_type=ht_kb&#038;p=34672"},"modified":"2026-06-09T10:51:26","modified_gmt":"2026-06-09T10:51:26","slug":"smtp-error-554-transaction-failed-how-to-fix-it","status":"publish","type":"ht_kb","link":"https:\/\/1grid.co.za\/knowledge\/smtp-error-554-transaction-failed-how-to-fix-it\/","title":{"rendered":"SMTP Error 554: Transaction Failed (How to Fix It)"},"content":{"rendered":"\n<p class=\"wp-block-paragraph\">If you\u2019ve received <strong>SMTP Error 554: Transaction Failed<\/strong>, it means the receiving mail server permanently rejected your email.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">This guide will:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li id=\"htoc-explain-what-smtp-554-actually-means\">Explain what SMTP 554 actually means<\/li>\n\n\n\n<li id=\"htoc-help-you-identify-the-specific-cause\">Help you identify the specific cause<\/li>\n\n\n\n<li id=\"htoc-show-you-how-to-fix-the-issue-safely\">Show you how to fix the issue safely<\/li>\n\n\n\n<li id=\"htoc-clarify-whether-the-problem-is-on-your-side-or-the-recipient-s\">Clarify whether the problem is on your side or the recipient\u2019s<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">By the end of this guide, you\u2019ll confidently diagnose and resolve SMTP 554 errors without unnecessary support escalation.<\/p>\n\n\n<div class=\"wp-block-image\">\n<figure class=\"aligncenter size-full\"><img loading=\"lazy\" decoding=\"async\" width=\"1600\" height=\"600\" src=\"https:\/\/1grid.co.za\/knowledge\/wp-content\/uploads\/2026\/06\/1-grid-Images-for-KB-Articles-1000-x-600-px-20.png\" alt=\"SMTP Error 554: Transaction Failed (How to Fix It)\" class=\"wp-image-34673\"\/><\/figure>\n<\/div>\n\n\n<div class=\"wp-block-ht-block-toc is-style-rounded htoc htoc--position-wide toc-list-style-plain\" data-htoc-state=\"expanded\"><span class=\"htoc__title\"><span class=\"ht_toc_title\">Quick Links<\/span><span class=\"htoc__toggle\"><svg xmlns=\"http:\/\/www.w3.org\/2000\/svg\" width=\"16\" height=\"16\"><g fill=\"#444\"><path d=\"M15 7H1c-.6 0-1 .4-1 1s.4 1 1 1h14c.6 0 1-.4 1-1s-.4-1-1-1z\"><\/path><path d=\"M15 1H1c-.6 0-1 .4-1 1s.4 1 1 1h14c.6 0 1-.4 1-1s-.4-1-1-1zM15 13H1c-.6 0-1 .4-1 1s.4 1 1 1h14c.6 0 1-.4 1-1s-.4-1-1-1z\"><\/path><\/g><\/svg><\/span><\/span><div class=\"htoc__itemswrap\"><ul class=\"ht_toc_list\"><li class=\"\"><a href=\"#htoc-step-by-step-fix-for-smtp-554-error-transaction-failed-permanent-reject\">Step-by-Step Fix for SMTP 554 Error &#8211; Transaction Failed \/ Permanent Reject<\/a><\/li><li class=\"\"><a href=\"#htoc-quick-fixes-for-common-smtp-554-variations\">Quick Fixes for Common SMTP 554 Variations<\/a><\/li><li class=\"\"><a href=\"#htoc-advanced-optional-fixes-for-technical-users\">Advanced (Optional) Fixes (For Technical Users)<\/a><\/li><\/ul><\/div><\/div>\n\n\n\n<h2 id=\"htoc-what-smtp-error-554-means\" class=\"wp-block-heading\">What SMTP Error 554 Means<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">SMTP 554 is a<strong> permanent rejection (<a href=\"https:\/\/1grid.co.za\/knowledge\/why-emails-bounce-back-error-messages-and-how-to-fix-them\/#htoc-hard-bounce-permanent-failure\" target=\"_blank\" rel=\"noreferrer noopener\">h<\/a><a href=\"https:\/\/1grid.co.za\/knowledge\/why-emails-bounce-back-error-messages-and-how-to-fix-them\/#htoc-hard-bounce-permanent-failure\">ard bounce<\/a>)<\/strong>.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Unlike temporary delivery delays, a 554 response means:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li id=\"htoc-the-receiving-server-refused-the-message-and-will-not-retry-delivery\">The receiving server refused the message and will not retry delivery.<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">However, 554 is often used as a generic \u201ccatch-all\u201d code, meaning the real reason appears in the extended message (e.g., 5.7.1, 5.7.9, etc.).<\/p>\n\n\n\n<h2 id=\"htoc-why-this-matters\" class=\"wp-block-heading\">Why This Matters<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">If ignored, repeated 554 errors can:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li id=\"htoc-prevent-important-emails-from-being-delivered\">Prevent important emails from being delivered<\/li>\n\n\n\n<li id=\"htoc-damage-your-domain-or-ip-reputation\">Damage your domain or IP reputation<\/li>\n\n\n\n<li id=\"htoc-trigger-spam-or-security-flags-on-recipient-servers\">Trigger spam or security flags on recipient servers<\/li>\n\n\n\n<li id=\"htoc-reduce-overall-email-deliverability-over-time\">Reduce overall email deliverability over time<\/li>\n\n\n\n<li id=\"htoc-cause-clients-or-customers-to-lose-trust-in-your-communication\">Cause clients or customers to lose trust in your communication<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">SMTP 554 is a permanent rejection so the message will not retry automatically.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Understanding the \u201cwhy\u201d ensures you fix the root cause, and not just resend the email and hope it works.<\/p>\n\n\n\n<h2 id=\"htoc-step-by-step-fix-for-smtp-554-error-transaction-failed-permanent-reject\" class=\"wp-block-heading\">Step-by-Step Fix for SMTP 554 Error &#8211; Transaction Failed \/ Permanent Reject<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Follow these steps in order.<\/p>\n\n\n\n<details class=\"wp-block-details is-layout-flow wp-block-details-is-layout-flow\"><summary><strong>1: Confirm the Full Error Message<\/strong><\/summary>\n<p class=\"wp-block-paragraph\" id=\"htoc-open-the-bounce-notification\">Open the bounce notification.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\" id=\"htoc-look-for-variations-such-as\">Variations:<\/p>\n\n\n\n<pre id=\"htoc-554-transaction-failed-554-5-7-1-message-rejected-554-relay-access-denied-554-message-refused-554-permanent-failure\" class=\"wp-block-code\"><code>554 Transaction failed\n554 5.7.1 Message rejected\n554 Relay access denied\n554 Message refused\n554 Permanent failure<\/code><\/pre>\n\n\n\n<p class=\"wp-block-paragraph\" id=\"htoc-the-extended-5-x-x-code-is-important\">The extended 5.x.x code is important.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\" id=\"htoc-if-another-smtp-code-appears-refer-to-our-smtp-error-codes-guide\">If another SMTP code appears, refer to our<strong> <a href=\"https:\/\/1grid.co.za\/knowledge\/a-guide-to-smtperror-codes\/\">SMTP Error Codes<\/a> <\/strong>guide.<\/p>\n<\/details>\n\n\n\n<details class=\"wp-block-details is-layout-flow wp-block-details-is-layout-flow\"><summary><strong>2: Identify the Rejection Reason<\/strong><\/summary>\n<p class=\"wp-block-paragraph\" id=\"htoc-mtp-554-usually-indicates-a-permanent-block-due-to\">SMTP 554 usually indicates a permanent block due to:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li id=\"htoc-spam-policy-violation\">Spam policy violation<\/li>\n\n\n\n<li id=\"htoc-authentication-failure\">Authentication failure<\/li>\n\n\n\n<li id=\"htoc-ip-reputation-issue\">IP reputation issue<\/li>\n\n\n\n<li id=\"htoc-relay-restrictions\">Relay restrictions<\/li>\n\n\n\n<li id=\"htoc-message-content-filtering\">Message content filtering<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\" id=\"htoc-carefully-read-the-extended-error-message\">Carefully read the extended error message.<\/p>\n<\/details>\n\n\n\n<details class=\"wp-block-details is-layout-flow wp-block-details-is-layout-flow\"><summary><strong>3: Simplify the Email Content<\/strong><\/summary>\n<p class=\"wp-block-paragraph\" id=\"htoc-if-content-filtering-is-suspected\">If <strong><a href=\"https:\/\/1grid.co.za\/knowledge\/email-security-spam-prevention\/\" target=\"_blank\" rel=\"noreferrer noopener\">content filtering<\/a> <\/strong>is suspected:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Remove excessive links<\/li>\n\n\n\n<li>Avoid all caps<\/li>\n\n\n\n<li>Remove suspicious attachments<\/li>\n\n\n\n<li>Send a plain-text test email<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\" id=\"htoc-if-the-test-succeeds-content-likely-triggered-the-block\">If the test succeeds, content likely triggered the block.<\/p>\n<\/details>\n\n\n\n<details class=\"wp-block-details is-layout-flow wp-block-details-is-layout-flow\"><summary><strong>4: Verify Authentication and DNS<\/strong><\/summary>\n<p class=\"wp-block-paragraph\" id=\"htoc-step-4-verify-authentication-and-dns\">Ensure: <\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li id=\"htoc-smtp-authentication-is-enabled\"><a href=\"https:\/\/1grid.co.za\/knowledge\/outlook-how-to-enable-smtp-authentication\/\"><strong>SMTP authenticatio<\/strong><\/a><a href=\"https:\/\/1grid.co.za\/knowledge\/outlook-how-to-enable-smtp-authentication\/\" target=\"_blank\" rel=\"noreferrer noopener\"><strong>n<\/strong><\/a> is enabled<\/li>\n\n\n\n<li id=\"htoc-spf-record-is-correct\"><a href=\"https:\/\/1grid.co.za\/knowledge\/?s=spf&amp;ht-kb-search=1&amp;lang=\" target=\"_blank\" rel=\"noreferrer noopener\"><strong>S<\/strong><\/a><a href=\"https:\/\/1grid.co.za\/knowledge\/?s=spf&amp;ht-kb-search=1&amp;lang=\"><strong>PF<\/strong><\/a> record is correct<\/li>\n\n\n\n<li id=\"htoc-dkim-is-active\"><strong><a href=\"https:\/\/1grid.co.za\/knowledge\/?s=spf&amp;ht-kb-search=1&amp;lang=\" target=\"_blank\" rel=\"noreferrer noopener\">D<\/a><a href=\"https:\/\/1grid.co.za\/knowledge\/?s=spf&amp;ht-kb-search=1&amp;lang=\">KIM<\/a> <\/strong>is active<\/li>\n\n\n\n<li id=\"htoc-dmarc-if-configured-is-valid\"><strong><a href=\"https:\/\/1grid.co.za\/knowledge\/cpanel-how-to-add-dmarc-record\/\" target=\"_blank\" rel=\"noreferrer noopener\">DMARC<\/a> <\/strong>(if configured) is valid<\/li>\n\n\n\n<li id=\"htoc-you-are-using-port-465-or-587-with-ssl-tls\">You are using port 465 or 587 with <a href=\"https:\/\/1grid.co.za\/knowledge\/understanding-smtp-ports-and-ssltls-encryption\/\"><strong>SSL\/TLS<\/strong><\/a><\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\" id=\"htoc-step-4-verify-authentication-and-dns1\">Authentication misalignment frequently causes 554 errors.<\/p>\n<\/details>\n\n\n\n<details class=\"wp-block-details is-layout-flow wp-block-details-is-layout-flow\"><summary><strong>5: Check IP Reputation (If Applicable)<\/strong><\/summary>\n<ul class=\"wp-block-list\">\n<li id=\"htoc-check-whether-your-sending-ip-is-listed-on-any-blocklists\">Check whether your sending<strong> <a href=\"https:\/\/1grid.co.za\/knowledge\/how-to-check-if-my-ip-is-blacklisted\/\">IP is listed on any blockl<\/a><a href=\"https:\/\/1grid.co.za\/knowledge\/how-to-check-if-my-ip-is-blacklisted\/\" target=\"_blank\" rel=\"noreferrer noopener\">ists<\/a><\/strong><\/li>\n\n\n\n<li id=\"htoc-confirm-reverse-dns-ptr-is-configured\">Confirm reverse DNS (PTR) is configured<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\" id=\"htoc-\">It is always recommended to monitor your IP reputation and health regularly.<\/p>\n<\/details>\n\n\n\n<details class=\"wp-block-details is-layout-flow wp-block-details-is-layout-flow\"><summary><strong>6: Review Delivery Logs (Basic Level)<\/strong><\/summary>\n<p class=\"wp-block-paragraph\" id=\"htoc-log-in-to\">Log in to:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong><a href=\"https:\/\/1grid.co.za\/knowledge\/how-to-log-in-to-cpanel-via-your-1-grid-customer-zone\/\" target=\"_blank\" rel=\"noreferrer noopener\">cPanel<\/a>&nbsp;<\/strong>\u2192 Email \u2192&nbsp;<strong><a href=\"https:\/\/1grid.co.za\/knowledge\/cpanel-how-to-view-delivery-reports-via-track-delivery\/\" target=\"_blank\" rel=\"noreferrer noopener\">Track Delivery<\/a>&nbsp;<\/strong><\/li>\n\n\n\n<li><strong><a href=\"https:\/\/1grid.co.za\/knowledge\/plesk-how-do-i-login-via-customer-zone\/\" target=\"_blank\" rel=\"noreferrer noopener\">Plesk<\/a>&nbsp;<\/strong>\u2192&nbsp;Websites &amp; Domains \u2192 Select your domain \u2192 Mail \u2192 Track Email Delivery&nbsp;<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\" id=\"htoc-confirm\">Confirm:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Permanent rejection (554)<\/li>\n\n\n\n<li>Specific policy or spam message returned<\/li>\n<\/ul>\n<\/details>\n\n\n\n<h2 id=\"htoc-quick-fixes-for-common-smtp-554-variations\" class=\"wp-block-heading\">Quick Fixes for Common SMTP 554 Variations<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">SMTP 554 is a <strong>permanent rejection<\/strong> (\u201chard bounce\u201d). This means that the receiving server refused the message, and it was not queued for delivery.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Unlike temporary errors (4xx), 554 requires action before the email can be resent.<\/p>\n\n\n\n<details class=\"wp-block-details is-layout-flow wp-block-details-is-layout-flow\"><summary><strong>1. 554 Invalid Recipient<\/strong><\/summary>\n<p class=\"wp-block-paragraph\" id=\"htoc-1-554-invalid-recipient\"><strong>Example: <\/strong><\/p>\n\n\n\n<pre id=\"htoc-554-invalid-recipient-554-sorry-no-mailbox-here-by-that-name-554-no-valid-recipients\" class=\"wp-block-code\"><code>554 Invalid recipient <br>554 Sorry, no mailbox here by that name. <br>554 No valid recipients<\/code><\/pre>\n\n\n\n<p class=\"wp-block-paragraph\" id=\"htoc-what-it-means-the-recipient-email-address-does-not-exist-or-is-disabled\"><strong>What It Means: <\/strong><br>The recipient email address does not exist or is disabled.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\" id=\"htoc-how-to-fix-it\"><strong>How to Fix It:<\/strong><\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li id=\"htoc-double-check-the-spelling-of-the-email-address\">Double-check the spelling of the email address<\/li>\n\n\n\n<li id=\"htoc-confirm-the-recipient-mailbox-is-active\">Confirm the recipient mailbox is active<\/li>\n\n\n\n<li id=\"htoc-ask-the-recipient-to-verify-their-correct-email\">Ask the recipient to verify their correct email<\/li>\n\n\n\n<li id=\"htoc-remove-invalid-addresses-from-mailing-lists\">Remove invalid addresses from mailing lists<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\" id=\"htoc-reassurance-this-does-not-aff\"><strong>Reassurance: <\/strong>This does <strong>not affect your hosting or mailbox<\/strong>. It only affects this specific message.<\/p>\n<\/details>\n\n\n\n<details class=\"wp-block-details is-layout-flow wp-block-details-is-layout-flow\"><summary><strong>2. 554 5.7.1 Message Blocked Due to Spam Content<\/strong><\/summary>\n<p class=\"wp-block-paragraph\" id=\"htoc-2-554-5-7-1-message-blocked-due-to-spam-content\"><strong>Example: <\/strong><\/p>\n\n\n\n<pre id=\"htoc-54-5-7-1-message-blocked-due-to-spam-content-554-rejected-due-to-spam-content-554-spam-detected\" class=\"wp-block-code\"><code>54 5.7.1 Message blocked due to spam content <br>554 rejected due to spam content <br>554 Spam detected<\/code><\/pre>\n\n\n\n<p class=\"wp-block-paragraph\" id=\"htoc-what-it-means-the-receiving-server-s-spam-filter-flagged-your-email-content\"><strong>What It Means: <\/strong><br>The receiving server\u2019s spam filter flagged your email content.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\" id=\"htoc-this-can-be-triggered-by\"><strong>Potential Triggers:<\/strong><\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li id=\"htoc-suspicious-links\">Suspicious links<\/li>\n\n\n\n<li id=\"htoc-spam-like-wording\">Spam-like wording<\/li>\n\n\n\n<li id=\"htoc-large-attachments\">Large attachments<\/li>\n\n\n\n<li id=\"htoc-blacklisted-sending-ip\">Blacklisted sending IP<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\" id=\"htoc-how-to-fix-it1\"><strong>How to Fix It:<\/strong><\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li id=\"htoc-remove-shortened-or-suspicious-links\">Remove shortened or suspicious links<\/li>\n\n\n\n<li id=\"htoc-reduce-excessive-formatting-or-all-caps\">Reduce excessive formatting or ALL CAPS<\/li>\n\n\n\n<li id=\"htoc-remove-large-attachments-or-use-cloud-sharing\">Remove large attachments (or use cloud sharing)<\/li>\n\n\n\n<li id=\"htoc-scan-your-website-and-device-for-malware\">Scan your website and device for malware<\/li>\n\n\n\n<li id=\"htoc-run-a-blacklist-check-on-your-sending-ip\">Run a blacklist check on your sending IP<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\" id=\"htoc-if-sending-marketing-email-review-your-list-hygiene-and-sending-practices\">If sending marketing email, review your list hygiene and sending practices.<\/p>\n<\/details>\n\n\n\n<details class=\"wp-block-details is-layout-flow wp-block-details-is-layout-flow\"><summary><strong>3. 554 5.7.1 Relay Access Denied<\/strong><\/summary>\n<p class=\"wp-block-paragraph\" id=\"htoc-example-554-lt-sender-example-com-gt-relay-access-denied\"><strong>Example: <\/strong><\/p>\n\n\n\n<pre id=\"htoc-example-554-lt-sender-example-com-gt-relay-access-denied1\" class=\"wp-block-code\"><code>554 &lt;sender@example.com&gt;: Relay access denied<\/code><\/pre>\n\n\n\n<p class=\"wp-block-paragraph\" id=\"htoc-what-it-means-your-smtp-authentication-is-failing-or-not-enabled\"><strong>What It Means: <\/strong><br>Your SMTP authentication is failing or not enabled.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\" id=\"htoc-the-server-does-not-recognise-you-as-an-authorised-sender\">The server does not recognise you as an authorised sender.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\" id=\"htoc-how-to-fix-it11\"><strong>How to Fix It:<\/strong><\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Ensure SMTP authentication is enabled<\/li>\n\n\n\n<li>Use the full email address as username<\/li>\n\n\n\n<li>Confirm the correct password<\/li>\n\n\n\n<li>Verify SSL\/TLS is enabled<\/li>\n\n\n\n<li>Confirm the correct SMTP port (465 or 587)<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\" id=\"htoc-if-the-password-was-recently-changed-update-it-on-all-devices\">If the password was recently changed, update it on all devices.<\/p>\n<\/details>\n\n\n\n<details class=\"wp-block-details is-layout-flow wp-block-details-is-layout-flow\"><summary><strong>4. 554 5.7.9 Message Not Accepted for Policy Reasons<\/strong><\/summary>\n<p class=\"wp-block-paragraph\" id=\"htoc-example-554-message-not-accepted-for-policy-reasons\"><strong>Example: <\/strong><\/p>\n\n\n\n<pre id=\"htoc-example-554-message-not-accepted-for-policy-reasons1\" class=\"wp-block-code\"><code>554 Message not accepted for policy reasons<\/code><\/pre>\n\n\n\n<p class=\"wp-block-paragraph\" id=\"htoc-what-it-means-the-recipient-server-rejected-the-message-due-to-internal-security-or-policy-rules\"><strong>What It Means: <\/strong><br>The recipient server rejected the message due to internal security or policy rules.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\" id=\"htoc-common-causes\"><strong>Common Causes:<\/strong><\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Missing SPF\/DKIM<\/li>\n\n\n\n<li>DMARC enforcement<\/li>\n\n\n\n<li>IP reputation issues<\/li>\n\n\n\n<li>Geo-blocking<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\" id=\"htoc-how-to-fix-it111\"><strong>How to Fix It:<\/strong><\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Verify SPF record is correct<\/li>\n\n\n\n<li>Confirm DKIM is enabled<\/li>\n\n\n\n<li>Check DMARC policy settings<\/li>\n\n\n\n<li>Run a blacklist check<\/li>\n\n\n\n<li>Contact the recipient\u2019s postmaster if necessary<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\" id=\"htoc-advanced-users-may-need-dns-adjustments\">Advanced users may need DNS adjustments.<\/p>\n<\/details>\n\n\n\n<details class=\"wp-block-details is-layout-flow wp-block-details-is-layout-flow\"><summary><strong>5. 554 5.7.0 Message Size Violation<\/strong><\/summary>\n<p class=\"wp-block-paragraph\" id=\"htoc-what-it-means-your-email-exceeds-the-recipient-s-size-limit\"><strong>What It Means:<\/strong> <br>Your email exceeds the recipient\u2019s size limit.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\" id=\"htoc-how-to-fix-it1111\"><strong>How to Fix It:<\/strong><\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Compress attachments<\/li>\n\n\n\n<li>Use cloud storage instead<\/li>\n\n\n\n<li>Keep total email size under 20\u201325MB<\/li>\n<\/ul>\n<\/details>\n\n\n\n<details class=\"wp-block-details is-layout-flow wp-block-details-is-layout-flow\"><summary><strong>6. 554 Malformed Mail \/ Not RFC Compliant<\/strong><\/summary>\n<p class=\"wp-block-paragraph\" id=\"htoc-example\"><strong>Example:<\/strong><\/p>\n\n\n\n<pre id=\"htoc-554-message-is-not-rfc-compliant-missing-date-header-554-malformed-mail-denied\" class=\"wp-block-code\"><code>554 Message is not RFC compliant; missing \"Date\" header 554 Malformed mail denied<\/code><\/pre>\n\n\n\n<p class=\"wp-block-paragraph\" id=\"htoc-what-it-means-the-message-format-violates-email-protocol-standards\"><strong>What It Means: <\/strong><br>The message format violates email protocol standards.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\" id=\"htoc-common-causes1\"><strong>Common Causes:<\/strong><\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Custom scripts<\/li>\n\n\n\n<li>Misconfigured SMTP libraries<\/li>\n\n\n\n<li>Incorrect line endings (bare LF instead of CRLF)<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\" id=\"htoc-how-to-fix-it11111\"><strong>How to Fix It:<\/strong><\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Ensure your application uses proper SMTP libraries<\/li>\n\n\n\n<li>Update your mail script<\/li>\n\n\n\n<li>Verify headers include Date, From, To, Message-ID<\/li>\n\n\n\n<li>Check CRLF line endings<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\" id=\"htoc-advanced-developers-may-need-to-review-the-mailer-configuration\"><strong>Advanced: <\/strong>Developers may need to review the mailer configuration.<\/p>\n<\/details>\n\n\n\n<details class=\"wp-block-details is-layout-flow wp-block-details-is-layout-flow\"><summary><strong>7. 554 Virus Found \/ Security Rejection<\/strong><\/summary>\n<p class=\"wp-block-paragraph\" id=\"htoc-example1\"><strong>Example: <\/strong><\/p>\n\n\n\n<pre id=\"htoc-554-rejected-due-to-virus-554-virus-found-message-permanently-rejected\" class=\"wp-block-code\"><code>554 rejected due to virus \n554 Virus found, message permanently rejected<\/code><\/pre>\n\n\n\n<p class=\"wp-block-paragraph\" id=\"htoc-what-it-means-the-message-or-attachment-triggered-antivirus-detection\"><strong>What It Means: <\/strong><br>The message or attachment triggered antivirus detection.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\" id=\"htoc-how-to-fix-it111111\"><strong>How to Fix It:<\/strong><\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Scan your device for malware<\/li>\n\n\n\n<li>Remove suspicious attachments<\/li>\n\n\n\n<li>Recreate the attachment file<\/li>\n\n\n\n<li>Verify your website is not compromised<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\" id=\"htoc-if-this-repeats-run-a-full-security-review\">If this repeats, run a full security review.<\/p>\n<\/details>\n\n\n\n<h2 id=\"htoc-advanced-optional-fixes-for-technical-users\" class=\"wp-block-heading\">Advanced (Optional) Fixes (For Technical Users)<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Administrators or Technical Users can identify permanent blocks, policy rejections, or spam-related failures.<\/p>\n\n\n\n<details class=\"wp-block-details is-layout-flow wp-block-details-is-layout-flow\"><summary><strong>1. Check Mail Logs for 554 Entries<\/strong><\/summary>\n<details class=\"wp-block-details is-layout-flow wp-block-details-is-layout-flow\"><summary><strong>Exim<\/strong><\/summary>\n<pre id=\"htoc-grep-554-var-log-exim-mainlog-tail-f-var-log-exim-mainlog\" class=\"wp-block-code\"><code>grep \"554\" \/var\/log\/exim_mainlog tail -f \/var\/log\/exim_mainlog<\/code><\/pre>\n<\/details>\n\n\n\n<details class=\"wp-block-details is-layout-flow wp-block-details-is-layout-flow\"><summary><strong>Postfix<\/strong><\/summary>\n<pre id=\"htoc-grep-554-var-log-maillog-tail-f-var-log-maillog\" class=\"wp-block-code\"><code>grep \"554\" \/var\/log\/maillog tail -f \/var\/log\/maillog<\/code><\/pre>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Goal: <\/strong>Determine cause: spam content, policy rejection, relay denied, or message size<\/p>\n<\/details>\n<\/details>\n\n\n\n<details class=\"wp-block-details is-layout-flow wp-block-details-is-layout-flow\"><summary><strong>2. Review Message Queue<\/strong><\/summary>\n<ul class=\"wp-block-list\">\n<li>Check for permanently rejected vs. deferred messages<\/li>\n\n\n\n<li>Remove permanently rejected messages if necessary<\/li>\n<\/ul>\n\n\n\n<details class=\"wp-block-details is-layout-flow wp-block-details-is-layout-flow\"><summary><strong>Exim<\/strong><\/summary>\n<pre id=\"htoc-exim-exim-bp-postfix-postqueue-p\" class=\"wp-block-code\"><code>exim -bp <\/code><\/pre>\n<\/details>\n\n\n\n<details class=\"wp-block-details is-layout-flow wp-block-details-is-layout-flow\"><summary><strong>Postfix<\/strong><\/summary>\n<pre id=\"htoc-exim-exim-bp-postfix-postqueue-p11\" class=\"wp-block-code\"><code>postqueue -p<\/code><\/pre>\n<\/details>\n<\/details>\n\n\n\n<details class=\"wp-block-details is-layout-flow wp-block-details-is-layout-flow\"><summary><strong>3. Verify SPF\/DKIM\/DMARC<\/strong><\/summary>\n<ul class=\"wp-block-list\">\n<li>Misaligned authentication often triggers 554<\/li>\n<\/ul>\n\n\n\n<pre id=\"htoc-dig-short-txt-example-com-spf-dig-short-txt-default-domainkey-example-com-dkim\" class=\"wp-block-code\"><code>dig +short TXT example.com # SPF \ndig +short TXT default._domainkey.example.com # DKIM<\/code><\/pre>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Confirm PTR (reverse DNS) records are correct<\/li>\n<\/ul>\n<\/details>\n\n\n\n<details class=\"wp-block-details is-layout-flow wp-block-details-is-layout-flow\"><summary><strong>4. Test with CLI <\/strong><\/summary>\n<pre id=\"htoc-swaks-to-recipient-example-com-server-mx-example-com-data-subject-test-n-nhello-telnet-mx-example-com-25\" class=\"wp-block-code\"><code>swaks --to recipient@example.com --server mx.example.com --data \n\"Subject: Test\\n\\nHello\" \ntelnet mx.example.com 25<\/code><\/pre>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Use this to confirm your server is accepted by recipient MTA<\/li>\n<\/ul>\n<\/details>\n\n\n\n<details class=\"wp-block-details is-layout-flow wp-block-details-is-layout-flow\"><summary><strong>5. Monitor Connection &amp; Throttling Limits<\/strong><\/summary>\n<ul class=\"wp-block-list\">\n<li id=\"htoc-check-simultaneous-smtp-connections\">Check simultaneous SMTP connections:<\/li>\n<\/ul>\n\n\n\n<pre id=\"htoc-netstat-anp-grep-25-lsof-i-25\" class=\"wp-block-code\"><code>netstat -anp | grep :25 \nlsof -i :25<\/code><\/pre>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Adjust MTA limits carefully:\n<ul class=\"wp-block-list\">\n<li><strong>Exim:<\/strong> smtp_accept_max<\/li>\n\n\n\n<li><strong>Postfix:<\/strong> default_process_limit, smtpd_client_connection_count_limit<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<\/details>\n\n\n\n<h2 id=\"htoc-before-you-move-on\" class=\"wp-block-heading\">Before You Move On<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">First confirm that the following has been checked and is as expected:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li id=\"htoc-the-recipient-address-is-correct\">The recipient address is correct<\/li>\n\n\n\n<li id=\"htoc-smtp-authentication-is-enabled\">SMTP authentication is enabled<\/li>\n\n\n\n<li id=\"htoc-spf-and-dkim-are-valid\">SPF and DKIM are valid<\/li>\n\n\n\n<li id=\"htoc-your-ip-is-not-blacklisted\">Your IP is not blacklisted<\/li>\n\n\n\n<li id=\"htoc-your-email-size-is-within-limits\">Your email size is within limits<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">Then resend the message.<\/p>\n\n\n\n<h2 id=\"htoc-advanced\" class=\"wp-block-heading\">(Advanced)<\/h2>\n\n\n\n<ul class=\"wp-block-list\">\n<li id=\"htoc-confirm-extended-5-7-x-error-details\">Confirm extended 5.7.x error details<\/li>\n\n\n\n<li id=\"htoc-verify-ip-reputation-and-authentication-alignment\">Verify IP reputation and authentication alignment<\/li>\n\n\n\n<li id=\"htoc-confirm-message-size-within-allowed-limits\">Confirm message size within allowed limits<\/li>\n<\/ul>\n\n\n\n<h2 id=\"htoc-if-this-didn-t-work\" class=\"wp-block-heading\">If This Didn\u2019t Work<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">If the bounce message includes:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li id=\"htoc-a-specific-ip-address\">A specific IP address<\/li>\n\n\n\n<li id=\"htoc-a-blacklist-reference\">A blacklist reference<\/li>\n\n\n\n<li id=\"htoc-a-policy-link-e-g-yahoo-postmaster\">A policy link (e.g. Yahoo Postmaster)<\/li>\n\n\n\n<li id=\"htoc-a-custom-server-rejection-code\">A custom server rejection code<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">You may need:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li id=\"htoc-dns-adjustments\">DNS adjustments<\/li>\n\n\n\n<li id=\"htoc-reputation-review\">Reputation review<\/li>\n\n\n\n<li id=\"htoc-recipient-server-assistance\">Recipient server assistance<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">If the issue persists:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li id=\"htoc-test-sending-a-simple-plain-text-email\">Test sending a simple plain-text email<\/li>\n\n\n\n<li id=\"htoc-remove-attachments\">Remove attachments<\/li>\n\n\n\n<li id=\"htoc-confirm-spf-dkim-configuration\">Confirm SPF\/DKIM configuration<\/li>\n\n\n\n<li id=\"htoc-review-sending-limits\">Review sending limits<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">If you are unsure how to interpret the bounce message, contact Support and include:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li id=\"htoc-the-full-bounce-message\">The full bounce message<\/li>\n\n\n\n<li id=\"htoc-the-time-sent\">The time sent<\/li>\n\n\n\n<li id=\"htoc-sender-and-recipient-addresses\">Sender and recipient addresses<\/li>\n<\/ul>\n\n\n\n<h2 id=\"htoc-common-mistakes-to-avoid\" class=\"wp-block-heading\">Common Mistakes to Avoid<\/h2>\n\n\n\n<ul class=\"wp-block-list\">\n<li id=\"htoc-using-mailbox-name-instead-of-full-email-address\">Using a mailbox name rather than the full email address<\/li>\n\n\n\n<li id=\"htoc-disabling-smtp-authentication\">Disabling SMTP authentication<\/li>\n\n\n\n<li id=\"htoc-sending-large-attachments-repeatedly\">Sending large attachments repeatedly<\/li>\n\n\n\n<li id=\"htoc-ignoring-blacklist-warnings\">Ignoring blacklist warnings<\/li>\n\n\n\n<li id=\"htoc-assuming-this-means-your-website-is-down\">Assuming this means your website is down<\/li>\n\n\n\n<li id=\"htoc-resending-the-same-blocked-content-repeatedly\">Resending the same blocked content repeatedly<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">SMTP 554 errors affect email delivery only, not your hosting environment.<\/p>\n\n\n\n<h2 id=\"htoc-empowering-insight\" class=\"wp-block-heading\">Empowering Insight<\/h2>\n\n\n<div class=\"wp-block-image\">\n<figure class=\"aligncenter size-full\"><img loading=\"lazy\" decoding=\"async\" width=\"1600\" height=\"300\" src=\"https:\/\/1grid.co.za\/knowledge\/wp-content\/uploads\/2026\/03\/1-grid-Images-for-KB-Articles-1000-x-600-px-1600-x-300-px.png\" alt=\"Empowering Insight\" class=\"wp-image-34464\"\/><\/figure>\n<\/div>\n\n\n<p class=\"wp-block-paragraph\">The key to resolving SMTP 554 is not the \u201c554\u201d itself: it\u2019s the extended message that follows it.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Read that line carefully before making changes.<\/p>\n\n\n\n<h2 id=\"htoc-next-recommended-steps\" class=\"wp-block-heading\">Next Recommended Steps<\/h2>\n\n\n\n<ul class=\"wp-block-list\">\n<li id=\"htoc-check-full-bounce-details\">Check Full Bounce Details<\/li>\n\n\n\n<li id=\"htoc-verify-recipient-address\">Verify Recipient Address<\/li>\n\n\n\n<li id=\"htoc-verify-recipient-address1\">Confirm SPF\/DKIM Records<\/li>\n\n\n\n<li id=\"htoc-run-blacklist-check\">Run<strong> <a href=\"https:\/\/www.google.com\/search?q=DNS-based+Blacklists&amp;rlz=1C1GCEU_enZA1059ZA1063&amp;oq=DNS-based+Blacklists&amp;gs_lcrp=EgZjaHJvbWUyBggAEEUYOdIBCDkyMmowajE1qAIIsAIB8QULYb83JOKbGPEFC2G_NyTimxg&amp;sourceid=chrome&amp;ie=UTF-8\">Blacklist Chec<\/a><a href=\"https:\/\/www.google.com\/search?q=DNS-based+Blacklists&amp;rlz=1C1GCEU_enZA1059ZA1063&amp;oq=DNS-based+Blacklists&amp;gs_lcrp=EgZjaHJvbWUyBggAEEUYOdIBCDkyMmowajE1qAIIsAIB8QULYb83JOKbGPEFC2G_NyTimxg&amp;sourceid=chrome&amp;ie=UTF-8\" target=\"_blank\" rel=\"noreferrer noopener\">k<\/a><\/strong><\/li>\n\n\n\n<li id=\"htoc-review-email-content\">Review Email Content<\/li>\n<\/ul>\n\n\n\n<h2 id=\"htoc-faqs\" class=\"wp-block-heading\">FAQs<\/h2>\n\n\n\n<details class=\"wp-block-details is-layout-flow wp-block-details-is-layout-flow\"><summary><strong>Q. Is this error permanent?<\/strong><\/summary>\n<p class=\"wp-block-paragraph\" id=\"htoc-q-is-this-error-permanent-yes-this-is-a-permanent-error-and-typically-requires-action-before-attempting-to-resend-again\">Yes, this is a permanent error and typically requires action before attempting to resend again.<\/p>\n<\/details>\n\n\n\n<details class=\"wp-block-details is-layout-flow wp-block-details-is-layout-flow\"><summary><strong>Q. Does 554 mean that I\u2019m blacklisted? <\/strong><\/summary>\n<p class=\"wp-block-paragraph\" id=\"htoc-q-does-554-mean-that-i-m-blacklisted-not-always-the-extended-error-message-will-confirm-this\">Not always. The extended error message will confirm this.<\/p>\n<\/details>\n\n\n\n<h2 id=\"htoc-additional-resources\" class=\"wp-block-heading\">Additional Resources <\/h2>\n\n\n\n<p class=\"wp-block-paragraph\"><strong><a href=\"https:\/\/1grid.co.za\/knowledge\/a-guide-to-smtperror-codes\/\" target=\"_blank\" rel=\"noreferrer noopener\">SMTP Error Codes<\/a>&nbsp;&nbsp;<\/strong><br><strong><a href=\"https:\/\/1grid.co.za\/knowledge\/how-to-enable-dkim-and-spf-on-your-mail-domain\/\" target=\"_blank\" rel=\"noreferrer noopener\">SPF\/DKIM Setup Guide<\/a>&nbsp;<\/strong>&nbsp;<br><strong><a href=\"https:\/\/1grid.co.za\/knowledge\/email-restrictions\/\" target=\"_blank\" rel=\"noreferrer noopener\">Email Sending Limits Guide<\/a>&nbsp;<\/strong>&nbsp;<br><strong><a href=\"https:\/\/1grid.co.za\/knowledge\/why-emails-bounce-back-error-messages-and-how-to-fix-them\/\" target=\"_blank\" rel=\"noreferrer noopener\">Email Bounce Back Guide<\/a>&nbsp;<\/strong><br><a href=\"https:\/\/1grid.co.za\/knowledge\/?s=spam&amp;ht-kb-search=1&amp;lang=\" target=\"_blank\" rel=\"noreferrer noopener\"><strong>Managing Spam Blocks<\/strong><\/a><br><a href=\"https:\/\/1grid.co.za\/knowledge\/?s=SPF&amp;ht-kb-search=1&amp;lang=\"><strong>SPF &amp; DKIM Managem<\/strong><\/a><a href=\"https:\/\/1grid.co.za\/knowledge\/?s=SPF&amp;ht-kb-search=1&amp;lang=\" target=\"_blank\" rel=\"noreferrer noopener\"><strong>ent<\/strong><\/a><br><a href=\"https:\/\/1grid.co.za\/knowledge\/what-is-ip-blacklisting\/\"><strong>IP Blacklisti<\/strong><\/a><a href=\"https:\/\/1grid.co.za\/knowledge\/what-is-ip-blacklisting\/\" target=\"_blank\" rel=\"noreferrer noopener\"><strong>ng<\/strong><\/a><\/p>\n\n\n\n<h2 id=\"htoc-need-additional-support\" class=\"wp-block-heading\">Need Additional Support?<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">We&#8217;re Here to<strong>&nbsp;<\/strong><a href=\"https:\/\/1grid.co.za\/knowledge\/\" target=\"_blank\" rel=\"noreferrer noopener\"><strong>Help<\/strong><\/a>:<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Understanding SMTP Error 554 and how to fix this doesn\u2019t have to feel technical with this easy-to-reference guide. Stuck? Check out our&nbsp;<a href=\"https:\/\/1grid.co.za\/knowledge\/1-grid-scope-of-support\/\" target=\"_blank\" rel=\"noreferrer noopener\"><strong>Scope of Support<\/strong><\/a>, and then contact our Support Team for&nbsp;further&nbsp;clarity and&nbsp;guidance&nbsp;(<a href=\"https:\/\/1grid.co.za\/contact-us\/\" target=\"_blank\" rel=\"noreferrer noopener\"><strong>https:\/\/1grid.co.za\/contact-us\/<\/strong><\/a>).&nbsp;We\u2019re&nbsp;ready&nbsp;to see&nbsp;how we can help!&nbsp;<\/p>\n","protected":false},"excerpt":{"rendered":"<p>If you\u2019ve received SMTP Error 554: Transaction Failed, it means the receiving mail server permanently rejected your email. This guide will: By the end of this guide, you\u2019ll confidently diagnose and resolve SMTP 554 errors without unnecessary support escalation. What SMTP Error 554 Means SMTP 554 is a permanent rejection&#8230;<\/p>\n","protected":false},"author":21,"comment_status":"closed","ping_status":"closed","template":"","format":"standard","meta":{"inline_featured_image":false,"footnotes":""},"ht-kb-category":[1194],"ht-kb-tag":[1759,1707,1761,1514,1760,1757,1706,1758,1701,1498],"class_list":["post-34672","ht_kb","type-ht_kb","status-publish","format-standard","hentry","ht_kb_category-email-troubleshooting","ht_kb_tag-554-transaction-failed","ht_kb_tag-email-delivery-issues","ht_kb_tag-email-rejected","ht_kb_tag-email-troubleshooting","ht_kb_tag-relay-access-denied","ht_kb_tag-smtp-544-fix","ht_kb_tag-smtp-bounce-errors","ht_kb_tag-smtp-error-554","ht_kb_tag-smtp-errors","ht_kb_tag-spam-block"],"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v22.0 - https:\/\/yoast.com\/wordpress\/plugins\/seo\/ -->\n<title>SMTP Error 554: Transaction Failed (How to Fix It) - 1-grid Knowledge Base<\/title>\n<meta name=\"description\" content=\"Fix SMTP Error 554 Transaction Failed. 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