{"id":34495,"date":"2026-03-10T12:19:07","date_gmt":"2026-03-10T12:19:07","guid":{"rendered":"https:\/\/1grid.co.za\/knowledge\/?post_type=ht_kb&#038;p=34495"},"modified":"2026-03-10T12:19:09","modified_gmt":"2026-03-10T12:19:09","slug":"why-emails-bounce-back-error-messages-and-how-to-fix-them","status":"publish","type":"ht_kb","link":"https:\/\/1grid.co.za\/knowledge\/why-emails-bounce-back-error-messages-and-how-to-fix-them\/","title":{"rendered":"Why Emails Bounce Back, Error Messages and How to Fix Them"},"content":{"rendered":"\n<p>Email bounce-back errors can feel frustrating, especially when the message&nbsp;doesn\u2019t&nbsp;clearly explain what went wrong. Most bounce errors do not mean something is broken.&nbsp;<\/p>\n\n\n\n<p>The good news? Bounce errors are common, and in most cases,\u00a0they\u2019re\u00a0temporary or easy to fix. Whether\u00a0you\u2019re\u00a0using\u00a0Shared Hosting\u00a0or a\u00a0Dedicated Server,\u00a0encountering\u00a0a bounce at some point is completely normal, and it\u00a0doesn\u2019t\u00a0mean your domain, website, or server is broken.\u00a0\u00a0<\/p>\n\n\n\n<p>Whether&nbsp;it\u2019s&nbsp;for personal or professional purposes,&nbsp;you\u2019ll&nbsp;be able to understand and ensure your emails always reach their destination.&nbsp;<\/p>\n\n\n\n<p>This guide will help you understand why emails bounce back and show you exactly what to do next.&nbsp;<\/p>\n\n\n\n<p>By the end,&nbsp;you\u2019ll&nbsp;be able to tell whether the issue is temporary or&nbsp;permanent and&nbsp;apply the correct fix confidently.&nbsp;<\/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\/03\/1-grid-Images-for-KB-Articles-1000-x-600-px-2-1.png\" alt=\"Email Bounce Back\" class=\"wp-image-34500\"\/><\/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\">Table of Contents<\/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-what-is-an-email-bounce-back\">What Is an Email Bounce Back?&nbsp;<\/a><\/li><li class=\"\"><a href=\"#htoc-hard-bounce-vs-soft-bounce-the-most-important-difference\">Hard Bounce vs Soft Bounce (The Most Important Difference)&nbsp;<\/a><ul class=\"ht_toc_child_list\"><li class=\"\"><a href=\"#htoc-hard-bounce-permanent-failure\">Hard Bounce (Permanent Failure)&nbsp;<\/a><\/li><li class=\"\"><a href=\"#htoc-soft-bounce-temporary-failure\">Soft Bounce (Temporary Failure)&nbsp;<\/a><\/li><\/ul><\/li><li class=\"\"><a href=\"#htoc-common-bounce-errors-with-quick-fixes\">Common Bounce Errors (With Quick Fixes)&nbsp;<\/a><ul class=\"ht_toc_child_list\"><li class=\"\"><a href=\"#htoc-550-mailbox-unavailable-user-unknown\">550 Mailbox Unavailable \/ User Unknown&nbsp;<\/a><\/li><li class=\"\"><a href=\"#htoc-554-transaction-failed\">554 Transaction Failed&nbsp;<\/a><\/li><li class=\"\"><a href=\"#htoc-530-authentication-required\">530 Authentication Required&nbsp;<\/a><\/li><li class=\"\"><a href=\"#htoc-send-limit-exceeded\">Send Limit Exceeded&nbsp;<\/a><\/li><li class=\"\"><a href=\"#htoc-spf-check-failed\">SPF Check Failed&nbsp;<\/a><\/li><\/ul><\/li><li class=\"\"><a href=\"#htoc-outlook-and-client-side-errors\">Outlook&nbsp;and&nbsp;Client-Side Errors&nbsp;<\/a><\/li><li class=\"\"><a href=\"#htoc-blacklists-and-ip-reputation\">Blacklists&nbsp;and&nbsp;IP Reputation&nbsp;<\/a><\/li><li class=\"\"><a href=\"#htoc-before-you-move-on\">Before You Move&nbsp;On&nbsp;&nbsp;<\/a><\/li><li class=\"\"><a href=\"#htoc-if-this-didn-t-work\">If This&nbsp;Didn\u2019t&nbsp;Work&nbsp;<\/a><\/li><li class=\"\"><a href=\"#htoc-common-mistakes-to-avoid\">Common Mistakes to Avoid&nbsp;<\/a><\/li><li class=\"\"><a href=\"#htoc-empowering-insight\">Empowering Insight&nbsp;<\/a><\/li><li class=\"\"><a href=\"#htoc-next-recommended-steps\">Next Recommended Steps&nbsp;<\/a><\/li><li class=\"\"><a href=\"#htoc-faqs\">FAQs&nbsp;<\/a><\/li><li class=\"\"><a href=\"#htoc-additional-resources\">Additional&nbsp;Resources&nbsp;<\/a><\/li><\/ul><\/div><\/div>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"htoc-what-is-an-email-bounce-back\"><strong>What Is an Email Bounce Back?<\/strong>&nbsp;<\/h2>\n\n\n\n<p>An email bounce back happens when your message cannot be\u00a0delivered,\u00a0and the receiving server sends a<strong>\u00a0<a href=\"https:\/\/blog.mxtoolbox.com\/2011\/09\/19\/non-delivery-report-or-backscatter-spam\/\">Non-Delivery Report (NDR)<\/a><\/strong>.\u00a0<\/p>\n\n\n\n<p>That report includes:&nbsp;<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li id=\"htoc-a-3-digit-smtp-code\">A 3-digit\u00a0<strong><a href=\"https:\/\/1grid.co.za\/knowledge\/a-guide-to-smtperror-codes\/\">SMTP code<\/a>\u00a0<\/strong><\/li>\n\n\n\n<li id=\"htoc-sometimes-an-extended-code-e-g-5-1-1\">Sometimes an<strong> <a href=\"https:\/\/1grid.co.za\/knowledge\/a-guide-to-smtperror-codes\/\">extended code<\/a> <\/strong>(e.g.\u00a05.1.1)\u00a0<\/li>\n\n\n\n<li id=\"htoc-a-short-explanation\">A short explanation\u00a0<\/li>\n<\/ul>\n\n\n\n<p>These codes are not&nbsp;random&nbsp;as&nbsp;they follow a structured system.&nbsp;<\/p>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"htoc-hard-bounce-vs-soft-bounce-the-most-important-difference\"><strong>Hard Bounce vs Soft Bounce (The Most Important Difference)<\/strong>&nbsp;<\/h2>\n\n\n\n<p>There are two main categories that types of email bounce back errors fall into, hard bounces and soft&nbsp;bounces, with the addition of blacklisting and general error messages.&nbsp;<\/p>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"htoc-hard-bounce-permanent-failure\"><strong>Hard Bounce (Permanent Failure)<\/strong>&nbsp;<\/h3>\n\n\n\n<p>The email cannot be&nbsp;delivered,&nbsp;and retrying&nbsp;won\u2019t&nbsp;help.&nbsp;<\/p>\n\n\n\n<details class=\"wp-block-details is-layout-flow wp-block-details-is-layout-flow\"><summary><strong>Common\u00a0Causes\u00a0<\/strong><\/summary>\n<ul class=\"wp-block-list\">\n<li>Invalid email address&nbsp;<\/li>\n\n\n\n<li id=\"htoc-mailbox-no-longer-exists\">Mailbox no longer exists&nbsp;<\/li>\n\n\n\n<li id=\"htoc-blocked-sender\">Blocked sender&nbsp;<\/li>\n\n\n\n<li id=\"htoc-domain-does-not-accept-mail\">Domain does not accept mail<\/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>Example\u00a0Codes\u00a0<\/strong><\/summary>\n<pre id=\"htoc-\" class=\"wp-block-code\"><code>550 Mailbox unavailable\u00a0\n554 Transaction failed\u00a0\n5.1.1 Bad destination mailbox<\/code><\/pre>\n<\/details>\n\n\n\n<details class=\"wp-block-details is-layout-flow wp-block-details-is-layout-flow\"><summary><strong>What to\u00a0Do If You Receive This Bounce Type<\/strong><\/summary>\n<ul class=\"wp-block-list\">\n<li id=\"htoc-double-check-the-recipient-address\">Double-check the recipient address&nbsp;<\/li>\n\n\n\n<li id=\"htoc-confirm-domain-exists\">Confirm the domain exists&nbsp;<\/li>\n\n\n\n<li id=\"htoc-review-spf-dkim\">Review SPF\/DKIM&nbsp;<\/li>\n\n\n\n<li id=\"htoc-check-blacklist-status\">Check blacklist status&nbsp;<\/li>\n<\/ul>\n<\/details>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"htoc-soft-bounce-temporary-failure\"><strong>Soft Bounce (Temporary Failure)<\/strong>&nbsp;<\/h3>\n\n\n\n<p>The email failed for\u00a0now, but\u00a0may succeed later.\u00a0<\/p>\n\n\n\n<details class=\"wp-block-details is-layout-flow wp-block-details-is-layout-flow\"><summary><strong>Common\u00a0Causes\u00a0<\/strong><\/summary>\n<ul class=\"wp-block-list\">\n<li>Mailbox full&nbsp;<\/li>\n\n\n\n<li id=\"htoc-server-temporarily-unavailable\">Server temporarily unavailable&nbsp;<\/li>\n\n\n\n<li id=\"htoc-greylisting\">Greylisting&nbsp;<\/li>\n\n\n\n<li id=\"htoc-message-too-large\">Message too large&nbsp;<\/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>Example\u00a0Codes<\/strong><\/summary>\n<pre id=\"htoc-1\" class=\"wp-block-code\"><code>421 Service not available\u00a0\n450 Mailbox unavailable\u00a0\n4.4.1 Connection timed out<\/code><\/pre>\n<\/details>\n\n\n\n<details class=\"wp-block-details is-layout-flow wp-block-details-is-layout-flow\"><summary><strong>What to\u00a0Do If You Receive This Bounce Type:\u00a0<\/strong><\/summary>\n<ul class=\"wp-block-list\">\n<li>Wait and retry&nbsp;<\/li>\n\n\n\n<li id=\"htoc-reduce-attachment-size\">Reduce attachment size&nbsp;<\/li>\n\n\n\n<li id=\"htoc-ask-recipient-to-free-space\">Ask the recipient to free up space&nbsp;<\/li>\n<\/ul>\n<\/details>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"htoc-common-bounce-errors-with-quick-fixes\"><strong>Common Bounce Errors (With Quick Fixes)<\/strong>&nbsp;<\/h2>\n\n\n\n<h6 class=\"wp-block-heading\" id=\"htoc-550-mailbox-unavailable-user-unknown\"><strong>550 Mailbox Unavailable \/ User Unknown<\/strong>&nbsp;<\/h6>\n\n\n\n<p><strong>Meaning:<\/strong>\u00a0Recipient address does not exist.\u00a0<\/p>\n\n\n\n<details class=\"wp-block-details is-layout-flow wp-block-details-is-layout-flow\"><summary><strong>Quick Fix\u00a0<\/strong><\/summary>\n<ul class=\"wp-block-list\">\n<li>Check spelling&nbsp;<\/li>\n\n\n\n<li id=\"htoc-confirm-mailbox-exists\">Confirm the mailbox exists&nbsp;<\/li>\n\n\n\n<li id=\"htoc-verify-mx-records\">Verify MX records&nbsp;<\/li>\n<\/ul>\n<\/details>\n\n\n\n<h6 class=\"wp-block-heading\" id=\"htoc-554-transaction-failed\"><strong>554 Transaction Failed<\/strong>&nbsp;<\/h6>\n\n\n\n<p><strong>Meaning:<\/strong>\u00a0Email rejected due to spam policy or sender reputation.\u00a0<\/p>\n\n\n\n<details class=\"wp-block-details is-layout-flow wp-block-details-is-layout-flow\"><summary><strong>Quick Fix<\/strong><\/summary>\n<ul class=\"wp-block-list\">\n<li>Check SPF&nbsp;and&nbsp;DKIM records&nbsp;<\/li>\n\n\n\n<li id=\"htoc-review-content-avoid-spam-wording\">Review content (avoid spam wording)&nbsp;<\/li>\n\n\n\n<li id=\"htoc-run-blacklist-check\">Run blacklist check&nbsp;<\/li>\n<\/ul>\n<\/details>\n\n\n\n<h6 class=\"wp-block-heading\" id=\"htoc-530-authentication-required\"><strong>530 Authentication Required<\/strong>&nbsp;<\/h6>\n\n\n\n<p><strong>Meaning:<\/strong>\u00a0Your email client is not logging in before sending.\u00a0<\/p>\n\n\n\n<details class=\"wp-block-details is-layout-flow wp-block-details-is-layout-flow\"><summary><strong>Quick Fix<\/strong><\/summary>\n<ul class=\"wp-block-list\">\n<li>Enable SMTP authentication&nbsp;<\/li>\n\n\n\n<li id=\"htoc-use-full-email-address-as-username\">Use the full email address as the username&nbsp;<\/li>\n\n\n\n<li id=\"htoc-reset-password\">Reset password<\/li>\n<\/ul>\n<\/details>\n\n\n\n<h6 class=\"wp-block-heading\" id=\"htoc-send-limit-exceeded\"><strong>Send Limit Exceeded<\/strong>&nbsp;<\/h6>\n\n\n\n<p><strong>Meaning:<\/strong>\u00a0You\u2019ve\u00a0exceeded hourly sending limits.\u00a0<\/p>\n\n\n\n<details class=\"wp-block-details is-layout-flow wp-block-details-is-layout-flow\"><summary><strong>Quick Fixes<\/strong><\/summary>\n<ul class=\"wp-block-list\">\n<li>Wait for the reset window&nbsp;<\/li>\n\n\n\n<li id=\"htoc-request-limit-review-if-business-critical\">Request a limit review if business-critical&nbsp;<\/li>\n<\/ul>\n<\/details>\n\n\n\n<h6 class=\"wp-block-heading\" id=\"htoc-spf-check-failed\"><strong>SPF Check Failed<\/strong>&nbsp;<\/h6>\n\n\n\n<p><strong>Meaning:<\/strong>\u00a0Your sending server is not authorised in your domain\u2019s SPF record.\u00a0<\/p>\n\n\n\n<details class=\"wp-block-details is-layout-flow wp-block-details-is-layout-flow\"><summary><strong>Quick Fix<\/strong><\/summary>\n<ul class=\"wp-block-list\">\n<li>Update SPF record&nbsp;<\/li>\n\n\n\n<li id=\"htoc-add-sending-server\">Add sending server&nbsp;<\/li>\n\n\n\n<li id=\"htoc-avoid-all-if-incorrectly-configured\">Avoid \u201c-all\u201d if incorrectly configured&nbsp;<\/li>\n<\/ul>\n<\/details>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"htoc-outlook-and-client-side-errors\"><strong>Outlook&nbsp;and&nbsp;Client-Side Errors<\/strong>&nbsp;<\/h2>\n\n\n\n<p>Some errors are device-related:&nbsp;<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>0x8004210B \u2192 Timeout sending&nbsp;<br>0x8004010f \u2192 Mailbox\/profile issue&nbsp;<br>SSL Certificate Warning \u2192 Hostname mismatch&nbsp;<br>IP Address Changed \u2192 Session invalidated&nbsp;<\/code><\/pre>\n\n\n\n<p>These do not mean your domain is broken&nbsp;\u2013 they just need some adjustments.&nbsp;<\/p>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"htoc-blacklists-and-ip-reputation\"><strong>Blacklists&nbsp;and&nbsp;IP Reputation<\/strong>&nbsp;<\/h2>\n\n\n\n<p>If your IP is blacklisted:&nbsp;<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li id=\"htoc-emails-may-be-rejected\">Emails may be rejected\u00a0<\/li>\n\n\n\n<li id=\"htoc-emails-may-land-in-spam\">Emails may land in spam\u00a0<\/li>\n\n\n\n<li id=\"htoc-delivery-may-fail-permanently\">Delivery may fail permanently\u00a0<\/li>\n<\/ul>\n\n\n\n<p>Monitor:&nbsp;<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li id=\"htoc-sender-reputation\">Sender reputation\u00a0<\/li>\n\n\n\n<li id=\"htoc-bounce-reports\">Bounce reports\u00a0<\/li>\n\n\n\n<li id=\"htoc-spam-complaints\">Spam complaints\u00a0<\/li>\n<\/ul>\n\n\n\n<p>Use blacklist check tools regularly.&nbsp;<\/p>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"htoc-before-you-move-on\"><strong>Before You Move&nbsp;On<\/strong><strong>&nbsp;<\/strong>&nbsp;<\/h2>\n\n\n\n<p>Ask:&nbsp;<\/p>\n\n\n\n<ol start=\"1\" class=\"wp-block-list\">\n<li id=\"htoc-does-the-error-start-with-4-temporary-or-5-permanent\">Does the error start with 4 (temporary) or 5 (permanent)?\u00a0<\/li>\n\n\n\n<li id=\"htoc-is-it-authentication-related1\">Is it\u00a0authentication-related?\u00a0<\/li>\n\n\n\n<li id=\"htoc-is-it-mailbox-related\">Is it\u00a0mailbox-related?\u00a0<\/li>\n\n\n\n<li id=\"htoc-is-it-reputation-related\">Is it reputation-related?\u00a0<\/li>\n<\/ol>\n\n\n\n<ol start=\"2\" class=\"wp-block-list\"><\/ol>\n\n\n\n<ol start=\"3\" class=\"wp-block-list\"><\/ol>\n\n\n\n<ol start=\"4\" class=\"wp-block-list\"><\/ol>\n\n\n\n<p>This narrows down most cases\u00a0immediately\u00a0and\u00a0provides\u00a0clear guidance on the right troubleshooting steps for the error that is causing the bounce back.\u00a0<\/p>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"htoc-if-this-didn-t-work\"><strong>If This&nbsp;Didn\u2019t&nbsp;Work<\/strong>&nbsp;<\/h2>\n\n\n\n<p>If your email is still bouncing after following the steps above\u00a0and troubleshooting the SMTP\u00a0error,\u00a0don\u2019t\u00a0worry,\u00a0we\u2019ll\u00a0help you get to the root of it.\u00a0<\/p>\n\n\n\n<details class=\"wp-block-details is-layout-flow wp-block-details-is-layout-flow\"><summary><strong>What to Gather Before Contacting Support<\/strong><\/summary>\n<p id=\"htoc-before-contacting-support-please-gather-the-following-to-speed-things-up\">Before contacting support, please gather the following to speed things up:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>The\u00a0<strong>full bounce-back message<\/strong>\u00a0(including the SMTP error code)\u00a0<\/li>\n\n\n\n<li>The\u00a0<strong>recipient\u2019s email address<\/strong>\u00a0<\/li>\n\n\n\n<li>The\u00a0<strong>time and date<\/strong>\u00a0the email was sent\u00a0<\/li>\n\n\n\n<li>Confirmation of whether this happens with one recipient or multiple recipients\u00a0\u00a0<\/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>Why This Helps<\/strong><\/summary>\n<p id=\"htoc-this-helps-us-determine-whether-the-issue-is-related-to\">This helps us&nbsp;determine&nbsp;whether the issue is related to:&nbsp;<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Mailbox availability\u00a0<\/li>\n\n\n\n<li>Authentication (SPF, DKIM, DMARC)\u00a0<\/li>\n\n\n\n<li>Blacklisting or reputation\u00a0<\/li>\n\n\n\n<li>Server configuration\u00a0<\/li>\n\n\n\n<li>Recipient-side restrictions\u00a0<\/li>\n<\/ul>\n<\/details>\n\n\n\n<p>We\u2019ll&nbsp;investigate from our side and guide you step-by-step to make sure you understand what caused it and how to prevent it in future.&nbsp;<\/p>\n\n\n\n<p>Bounce errors are common, and&nbsp;we\u2019re&nbsp;here to help you resolve them with clarity and confidence.&nbsp;<\/p>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"htoc-common-mistakes-to-avoid\"><strong>Common Mistakes to Avoid<\/strong>&nbsp;<\/h2>\n\n\n\n<ul class=\"wp-block-list\">\n<li id=\"htoc-resending-repeatedly-after-a-hard-bounce\">Resending repeatedly after a hard bounce\u00a0<\/li>\n\n\n\n<li id=\"htoc-ignoring-spf-dkim-configuration\">Ignoring SPF\/DKIM configuration\u00a0<\/li>\n\n\n\n<li id=\"htoc-sending-large-attachments\">Sending large attachments\u00a0<\/li>\n\n\n\n<li id=\"htoc-buying-email-lists\">Buying email lists\u00a0<\/li>\n\n\n\n<li id=\"htoc-disabling-ssl-to-test\">Disabling SSL to \u201ctest\u201d\u00a0<\/li>\n<\/ul>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"htoc-empowering-insight\"><strong>Empowering Insight<\/strong>&nbsp;<\/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>If you check the first digit of the error code, you immediately&nbsp;know&nbsp;whether to wait or take action.&nbsp;<\/p>\n\n\n\n<p>That one step prevents most panic.&nbsp;<\/p>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"htoc-next-recommended-steps\"><strong>Next Recommended Steps<\/strong>&nbsp;<\/h2>\n\n\n\n<ul class=\"wp-block-list\">\n<li id=\"htoc-review-the-full-bounce-message-identify-the-smtp-code\">Review the Full Bounce Message (Identify the SMTP code)\u00a0<\/li>\n\n\n\n<li id=\"htoc-verify-the-recipient-s-email-address\">Verify the Recipient\u2019s Email Address\u00a0<\/li>\n\n\n\n<li id=\"htoc-check-mailbox-storage-sender-and-recipient\">Check Mailbox Storage (Sender and Recipient)\u00a0<\/li>\n\n\n\n<li id=\"htoc-confirm-spf-dkim-and-dmarc-records\">Confirm SPF, DKIM\u00a0and\u00a0DMARC Records\u00a0<\/li>\n\n\n\n<li id=\"htoc-run-a-blacklist-check\">Run a Blacklist Check\u00a0<\/li>\n\n\n\n<li id=\"htoc-test-sending-to-an-alternative-recipient\">Test Sending to an Alternative Recipient\u00a0<\/li>\n\n\n\n<li id=\"htoc-contact-support-if-the-error-persists\">Contact Support if the Error Persists\u00a0<\/li>\n<\/ul>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"htoc-faqs\"><strong>FAQs<\/strong>&nbsp;<\/h2>\n\n\n\n<details class=\"wp-block-details is-layout-flow wp-block-details-is-layout-flow\"><summary><strong>Q. Do I need to be technical?\u00a0<\/strong><\/summary>\n<p id=\"htoc-q-do-i-need-to-be-technical-no-focus-on-whether-it-s-temporary-or-permanent\">No, focus on whether\u00a0it\u2019s\u00a0temporary or permanent.\u00a0<\/p>\n<\/details>\n\n\n\n<details class=\"wp-block-details is-layout-flow wp-block-details-is-layout-flow\"><summary><strong>Q. Why does Gmail reject my email?\u00a0<\/strong><\/summary>\n<p id=\"htoc-q-why-does-gmail-reject-my-email-often-spf-dkim-or-reputation-related-you-can-explore-more-information-on-this-here\">Often SPF\/DKIM or\u00a0reputation-related. You can explore more information on this\u00a0here.\u00a0<\/p>\n<\/details>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"htoc-additional-resources\"><strong>Additional&nbsp;Resources<\/strong>&nbsp;<\/h2>\n\n\n\n<p><strong><a href=\"https:\/\/1grid.co.za\/knowledge\/a-guide-to-smtperror-codes\/\" target=\"_blank\" rel=\"noreferrer noopener\">List of\u00a0SMTP\u00a0Error Codes<\/a>\u00a0<\/strong><br><a href=\"https:\/\/1grid.co.za\/knowledge\/spf-and-dkim-records-within-cpanel\/\" target=\"_blank\" rel=\"noreferrer noopener\"><strong>SPF\/DKIM Setup Guide\u00a0<\/strong><\/a><br><strong><a href=\"https:\/\/1grid.co.za\/knowledge\/how-to-check-if-my-ip-is-blacklisted\/\" target=\"_blank\" rel=\"noreferrer noopener\">Blacklist Checker Tool<\/a>\u00a0<\/strong><br><a href=\"https:\/\/1grid.co.za\/knowledge\/email-restrictions\/\" target=\"_blank\" rel=\"noreferrer noopener\"><strong>Email Sending Limits Guide\u00a0<\/strong><\/a><br><a href=\"http:\/\/Recommended Server Settings for Email (Encryption &amp; Ports)\" target=\"_blank\" rel=\"noreferrer noopener\"><strong>Recommended Server Settings for Em<\/strong><\/a><a href=\"https:\/\/1grid.co.za\/knowledge\/recommended-server-settings-for-email-encryption-ports\/\" target=\"_blank\" rel=\"noreferrer noopener\"><strong>ail<\/strong><\/a><\/p>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"htoc-need-additional-support\"><strong>Need Additional Support?<\/strong>&nbsp;<\/h2>\n\n\n\n<p><strong>We&#8217;re&nbsp;Here to&nbsp;<\/strong><a href=\"https:\/\/1grid.co.za\/knowledge\/\" target=\"_blank\" rel=\"noreferrer noopener\"><strong>Help<\/strong><\/a><strong>:<\/strong>&nbsp;<\/p>\n\n\n\n<p>Understanding&nbsp;why emails bounce back, error&nbsp;messages,&nbsp;and how to fix them&nbsp;doesn\u2019t&nbsp;have&nbsp;to&nbsp;feel technical&nbsp;with&nbsp;this&nbsp;easy-to-reference guide. Stuck?&nbsp;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&#8217;re&nbsp;ready&nbsp;to see&nbsp;how we can help!&nbsp;<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Email bounce-back errors can feel frustrating, especially when the message&nbsp;doesn\u2019t&nbsp;clearly explain what went wrong. Most bounce errors do not mean something is broken.&nbsp; The good news? Bounce errors are common, and in most cases,\u00a0they\u2019re\u00a0temporary or easy to fix. Whether\u00a0you\u2019re\u00a0using\u00a0Shared Hosting\u00a0or a\u00a0Dedicated Server,\u00a0encountering\u00a0a bounce at some point is completely normal, and&#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":[1692,138,1686,1482,1688,1690,1687,1689,1691],"class_list":["post-34495","ht_kb","type-ht_kb","status-publish","format-standard","hentry","ht_kb_category-email-troubleshooting","ht_kb_tag-authentication-error","ht_kb_tag-blacklist","ht_kb_tag-bounce-back-2","ht_kb_tag-email-errors","ht_kb_tag-hard-bounce","ht_kb_tag-mail-rejection","ht_kb_tag-smtp-error","ht_kb_tag-soft-bounce","ht_kb_tag-spf-failure"],"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v22.0 - https:\/\/yoast.com\/wordpress\/plugins\/seo\/ -->\n<title>Why Emails Bounce Back, Error Messages and How to Fix Them - 1-grid Knowledge Base<\/title>\n<meta name=\"description\" content=\"Learn why emails bounce back, what hard vs soft bounces mean, and how to fix common SMTP and authentication errors quickly.\" \/>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/1grid.co.za\/knowledge\/why-emails-bounce-back-error-messages-and-how-to-fix-them\/\" \/>\n<meta property=\"og:locale\" content=\"en_US\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"Why Emails Bounce Back, Error Messages and How to Fix Them - 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