{"id":3865,"date":"2024-04-17T11:34:54","date_gmt":"2024-04-17T11:34:54","guid":{"rendered":"https:\/\/www.warmy.io\/blog\/how-to-fix-smtp-email-error-552-5-3-4-solved\/"},"modified":"2026-04-04T13:33:11","modified_gmt":"2026-04-04T13:33:11","slug":"how-to-fix-smtp-email-error-552-5-3-4-solved","status":"publish","type":"post","link":"https:\/\/www.warmy.io\/blog\/how-to-fix-smtp-email-error-552-5-3-4-solved\/","title":{"rendered":"SMTP Error 552 5.3.4: Message Too Large \u2014 What It Means and How to Resolve It"},"content":{"rendered":"<p><span>In today\u2019s world, communicating without email seems nearly impossible. <\/span><\/p>\n<p><span>Email works through transmission via the <a href=\"https:\/\/www.warmy.io\/blog\/what-is-smtp-and-how-does-the-smtp-server-work\/\" target=\"_blank\" rel=\"noopener noreferrer\">Simple Mail Transfer Protocol<\/a> and here\u2019s a quick overview of how it works:<\/span><\/p>\n<ul>\n<li><span>When one sends an email, the sender\u2019s email client attempts to establish a connection with the SMTP server responsible for handling outgoing emails.\u00a0<\/span><\/li>\n<li>When the connection is established, the sender\u2019s email client communicates with with the SMTP server using specific commands.<\/li>\n<li>Examples of these commands include identifying the sender and recipient, providing the email content, and requesting the server to deliver the email.<\/li>\n<li>The SMTP server proceeds to process the email, conducts various checks, and attempts to deliver it to the recipient\u2019s mail server.<\/li>\n<\/ul>\n<p><span>Unfortunately, errors can occur from time to time.\u00a0 One such error is SMTP Error 552 5.3.4.\u00a0<\/span><\/p>\n<p>It results from interface limits breached with too large an attachment or an infraction-type message sent, like <a href=\"https:\/\/www.warmy.io\/blog\/why-are-my-emails-going-to-spam-junk-box-ways-to-prevent-solved\/\" target=\"_blank\" rel=\"noopener noreferrer\"><span>spam<\/span><\/a><span>. <\/span><\/p>\n<p><span>Furthermore, SMTP Email Error 552 5.3.4 may be connected to a more extensive email server failure\u2014whether it\u2019s a configuration error or a policy enhancement that might change other configurations which allow sending in the first place. Therefore, it\u2019s critical to assess what\u2019s wrong with this error.<\/span><\/p>\n<p><iframe width=\"640\" height=\"360\" src=\"https:\/\/www.youtube.com\/embed\/v77yHEPCzW0\" frameborder=\"0\" allowfullscreen allow=\"accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture; web-share\"><\/iframe><\/p>\n<h2>Demystifying SMTP Error 552 5.3.4<\/h2>\n<p><span>SMTP<\/span><span> Error 552 5.3.4 is one of those error messages that comes in various forms across different email clients and email servers, yet the meaning is consistent: <\/span><em><strong>Your email failed to send because it was too large. <\/strong><\/em><\/p>\n<ul>\n<li><span>If you\u2019re using Microsoft Outlook, you might see this: <em>\u201c552 5.3.4 Message size exceeds fixed limit.\u201d<\/em> <\/span><\/li>\n<li><span>If you\u2019re using Gmail, you\u2019ll get this message: <em>\u201cMessage rejected. Size exceeds maximum permitted.\u201d<\/em> <\/span><\/li>\n<\/ul>\n<p><span>Such error codes are relatively straightforward, letting you know your email did not go through.<\/span><\/p>\n<h3>Implications of SMTP Error 552 5.3.4 on email sending<\/h3>\n<ul>\n<li>\n<p><strong>Disruption of communication.<\/strong>\u00a0This error prevents the email from being delivered, which can interrupt timely communication, especially in professional or urgent contexts.<\/p>\n<\/li>\n<li>\n<p><strong>Need for content adjustment.<\/strong> Senders are then required to modify the email content before trying again, typically by reducing the size of attachments or splitting the content into multiple messages, in order to comply with server limitations.<\/p>\n<\/li>\n<li>\n<p><strong>Server policy awareness.<\/strong> This error underscores the importance of being aware of and adhering to specific mail server policies regarding email size, which can vary widely between different email providers or organizational email servers.<\/p>\n<\/li>\n<li>\n<p><strong>Potential for data loss. <\/strong>In scenarios where large files need to be shared, this error could lead to challenges in data transfer, pushing users to find alternative methods to share large files.<\/p>\n<\/li>\n<\/ul>\n<p><strong>\ud83d\udd16 Related Reading:<\/strong> <span><a href=\"https:\/\/www.warmy.io\/blog\/how-to-fix-smtp-email-error-552-solved\/\" rel=\"noopener\" target=\"_blank\">SMTP Email Error 552 \u2013 How to Resolve [SOLVED]<\/a><\/span><\/p>\n<h2>Exploring the reasons behind SMTP 552 5.3.4<\/p>\n<\/h2>\n<h3>Exceeding size limits<\/h3>\n<p><span>Most email servers limit the total size an email can be\u2014content and attachments\u2014and an SMTP Error 552 5.3.4 message is returned to the sender if the email exceeds the limit. <\/span><span>These limits are in place for resource management and the effectiveness of the system as a whole.<\/span><\/p>\n<h3>Large attachments<\/h3>\n<p><span>An email with a large attachment is the primary reason for going over the limit due to significant attachment sizes. <\/span><\/p>\n<p><span>For instance, high-quality photos, large documents, or videos will make it impractical to comply with limits set by email servers.<\/span><\/p>\n<h3>Embedded content in the email<\/h3>\n<p><span>In addition to attachments, embedding images or other media in the email will increase its size. More specifically, emails that are well-formatted with <\/span><span>HTML<\/span><span> with extensive inline styling or embedded media are more prone to being rejected.<\/span><\/p>\n<p><em>Q: What are HTML emails?<\/em><\/p>\n<p><em>A: HTML emails are emails formatted using HTML (HyperText Markup Language). This means emails have rich content\u2014including images, colors, links, and custom layouts. Compared to plain text emails, HTML emails are more visually appealing, but may not be necessarily better for email deliverability.<\/em><\/p>\n<p><strong>\ud83d\udd16 Related Reading: <\/strong><a href=\"https:\/\/www.warmy.io\/blog\/plain-text-or-html-in-cold-email\/\" target=\"_blank\" rel=\"noopener noreferrer\"><span>Plain text or HTML in cold email?<\/span><\/a><\/p>\n<h3>Server configuration<\/h3>\n<p><span>This issue may also be caused by the particular setup and rules of an email server. The size limitations of servers may differ depending on their specifications and the rules set forth by the hosting company or service.<\/span><\/p>\n<h3>Data accumulation<\/h3>\n<p><span>An email\u2019s size may occasionally grow unexpectedly due to the accumulation of header data from several forwarding instances or additional metadata.<\/span><\/p>\n<h2>Detailed solutions for resolving SMTP Error 552 5.3.4<br \/>\n<\/h2>\n<h3>Instructions for Gmail users<\/h3>\n<ol>\n<li>\n<p><strong>Check email size.<\/strong> It should not exceed 25 MB in total, including attached files. This is <a href=\"https:\/\/support.google.com\/mail\/answer\/6584?hl=en&amp;co=GENIE.Platform%3DDesktop#:~:text=You%20can%20send%20up%20to,Google%20Drive%20attachment%20sharing%20settings.\" rel=\"noopener\" target=\"_blank\" rel=\"noopener noreferrer\">Gmail\u2019s maximum allowable email size limit<\/a>.<\/p>\n<\/li>\n<li>\n<p><strong>Compress the attached files.<\/strong> To do this, you will need to create a ZIP archive for the file that you intend to attach to the email.<\/p>\n<\/li>\n<li>\n<p><strong>Use Google Drive.<\/strong> If the attached file is more than 25 MB, it would be better to upload the file to Google Drive and send the link in the email.<\/p>\n<\/li>\n<\/ol>\n<h3>For Outlook users<\/h3>\n<ol>\n<li>\n<p><strong>Verify <a href=\"https:\/\/support.microsoft.com\/en-us\/office\/reduce-attachment-size-to-send-large-files-with-outlook-8c698842-b462-4a4c-8d53-5c5dd04f77ef\" rel=\"noopener\" target=\"_blank\" rel=\"noopener noreferrer\">attachment limits<\/a>.<\/strong> Make sure the size of the email file does not exceed 20 MB if you use Outlook.<\/p>\n<\/li>\n<li>\n<p><strong>Compress larger files.<\/strong> For larger documents or pictures, it is recommended to compress them before attaching them to the email.<\/p>\n<\/li>\n<li>\n<p><strong>Finally, adjust Outlook settings.<\/strong> A user can also change the default server timeout in Outlook so the attached file can be sent as the longer timeout means less possibility of error.<\/p>\n<\/li>\n<\/ol>\n<h3>For Yahoo Mail users<\/h3>\n<ol>\n<li><strong>Limit email size.<\/strong> Ensure email size is no more than 25 MB, including attachments to fit <a href=\"https:\/\/help.yahoo.com\/kb\/SLN5673.html\" rel=\"noopener\" target=\"_blank\" rel=\"noopener noreferrer\">Yahoo email limits<\/a>.<\/li>\n<li><strong>Compress files<\/strong>. Use file compression software to minimize the size of the attachments you are intending to email.<\/li>\n<li><strong>Break down large emails.<\/strong> Split the attachments into smaller parts if they are too large and email each one in different messages as needed.<\/li>\n<\/ol>\n<h3>General tips<\/h3>\n<ol>\n<li>Remember to always verify the recipient\u2019s email capabilities as well, since certain email systems may have more stringent attachment size limits.<\/li>\n<li>When data security and secrecy are critical, think about using secure file transfer services or other alternate means when exchanging huge files.<\/li>\n<\/ol>\n<h2>Optimizing email management with Warmy.io<br \/>\n<\/h2>\n<p><span>SMTP errors, while inconvenient, are not the end of the world. Additionally, aside from implementing the tips above to avoid SMTP Error 552 5.3.4, senders can leverage the power of tools like <a href=\"http:\/\/Such services enable you to gradually begin sending lots of emails, and since their servers have exceeded limits or for other reasons, they won&#039;t deny your emails. For instance, Warmy.io adjusts your email limit so you position yourself as a trustworthy sender who will not have their emails denied merely because they&#039;re too big. On top of that, this service offers free deliverability tools like whether your emails can be delivered to the recipient\u2019s server or not, a domain blacklist checker, and a tool to generate SPF &amp; DMARC records. As a result, these tools can be leveraged not only to troubleshoot and remediate deliverability issues, but also help keep an email program running strong, to prevent it from faltering through neglect of the best practices common to even the most well-known established senders. Specifically, Warmy.io increases your email volume allowing you to create a sender reputation where your emails will not be rejected specifically for being too large. In addition to this, this service provides free deliverability tools such as a tool to check if your emails can be delivered to the recipient\u2019s server, a tool to check if your domain is put on a blacklist, and a tool that generates SPF and DMARC records. Therefore, these tools can be used for more than just troubleshooting and resolving deliverability problems \u2013 they can also assist in maintaining email performance so it doesn\u2019t deteriorate due to neglecting to comply with best practices archetypical of an already established sender.\" target=\"_blank\" rel=\"noopener noreferrer\">Warmy.io<\/a> to maximize their email deliverability potential.<\/span><\/p>\n<h3>Warmup process that&#8217;s automated yet done right<\/h3>\n<p><span>Warmy helps senders build a reputable sender reputation by gradually sending lots of emails. You will be positioned as a trustworthy sender who will not have their emails denied merely because they\u2019re too big.<\/span><\/p>\n<p><span>Warmy\u2019s email warmup works by:<\/span><\/p>\n<ul>\n<li><span>Automatically yet gradually increasing sending volume to build trust with mailbox providers.<\/span><\/li>\n<li><span>Simulating real human-like interactions\u2014emails are opened, replied to, and marked as important, boosting deliverability.<\/span><\/li>\n<li><span>Working across 30+ languages so your emails look natural and relevant for global audiences.<\/span><\/li>\n<\/ul>\n<p><img loading=\"lazy\" decoding=\"async\" alt=\"A performance graph on a light orange background shows email activity over time. Two lines represent Sent and Received emails, starting at zero and peaking at about 200. Labels indicate daily, weekly, and monthly metrics.\" height=\"600\" src=\"https:\/\/warmy-blog-wordpress-bucket.s3.amazonaws.com\/wp-content\/uploads\/2025\/03\/11093322\/8shots_so.png\" width=\"800\" title=\"\"><\/p>\n<h3>Customized warmup via Warmup Preferences feature<\/h3>\n<p><span>This feature is designed to make your email warmup process even smarter by allowing senders to tailor certain preferences, such as:<\/span><\/p>\n<ul>\n<li><span>\u00a0Warmup distribution across GSuite, Gmail, M365, Outlook, Yahoo, and even Private SMTP.<\/span><\/li>\n<li><span>Engagement patterns. Choose between B2B or B2C customers.<\/span><\/li>\n<li><span>Define percentage of emails that will be sent to each provider<\/span><\/li>\n<\/ul>\n<p><span>You can also set warmup settings for all your mailboxes at once\u2014or even one by one, whichever you prefer. Plus, a<\/span><span>ll settings can be changed directly within Warmy\u2019s system, so there\u2019s no need to contact support and wait<\/span><\/p>\n<p><img loading=\"lazy\" decoding=\"async\" alt=\"A dashboard displaying a profile section with a circular chart titled WARM-UP PREFERENCES. The chart shows percentages for Gmail, Outlook, G-Suite, Yahoo, and others. A table beneath lists specific percentages and email services.\" height=\"600\" src=\"https:\/\/warmy-blog-wordpress-bucket.s3.amazonaws.com\/wp-content\/uploads\/2025\/03\/11092845\/290shots_so-copy-1-1024x768.png\" width=\"800\" title=\"\"><\/p>\n<h3>Advanced seed lists for better inbox placement<\/h3>\n<p><span>Some warmup tools use fake email addresses, which do nothing for your reputation. Warmy.io\u2019s <a href=\"https:\/\/www.warmy.io\/product\/seed-list\" target=\"_blank\" rel=\"noopener noreferrer\">advanced seed lists<\/a> contain genuine email addresses which provide a<\/span><span>uthentic email interactions (opens, scrolls, clicks, replies, archives). <\/span><span>If an email lands in spam, it is removed and marked as important<\/span><\/p>\n<p><span>Other details about Warmy\u2019s seed lists:<\/span><\/p>\n<ul>\n<li><span>Better recognition by ISPs like Google, Microsoft, and Yahoo<\/span><\/li>\n<li><span>Improved sender score and reputation<\/span><\/li>\n<li><span>Available for Gmail, Outlook, and Yahoo.<\/span><\/li>\n<li><span>Ability to warm up using any provider that previously cannot be warmed up\u2014Mailchimp, Shopify, Omnisend, and Klaviyo, etc.<\/span><\/li>\n<\/ul>\n<p><a href=\"https:\/\/www.warmy.io\/product\/seed-list\" target=\"_blank\" rel=\"noopener noreferrer\"><span>Learn more about Warmy\u2019s seed lists here<\/span><\/a><span>. You can also get a more in-depth look at how Warmy\u2019s seed lists work by checking out these resources:<\/span><\/p>\n<ul>\n<li><a href=\"https:\/\/www.warmy.io\/blog\/email-warmup-alternatives-when-traditional-warmup-isnt-enough\/\" target=\"_blank\" rel=\"noopener noreferrer\"><span>Email Warmup Alternatives: When Traditional Warmup Isn\u2019t Enough<\/span><\/a><\/li>\n<li><a href=\"https:\/\/www.warmy.io\/blog\/email-engagement-how-seed-list-helps-improve-open-click-rates\/\" target=\"_blank\" rel=\"noopener noreferrer\"><span>Email Engagement How Seed List Helps Improve Open &amp; Click Rates<\/span><\/a><\/li>\n<\/ul>\n<p><img loading=\"lazy\" decoding=\"async\" alt=\"A beige interface displays options for selecting the number of seeds and senders with a slider and buttons. Below, a table compares features of Gmail, Outlook, and Yahoo seeds with checkmarks for various actions.\" height=\"600\" src=\"https:\/\/warmy-blog-wordpress-bucket.s3.amazonaws.com\/wp-content\/uploads\/2025\/03\/11093349\/430shots_so.webp\" width=\"800\" title=\"\"><\/p>\n<h3>Free email deliverability test for a clear direction<\/h3>\n<p><span>On top of all the features mentioned above,Warmy offers a<\/span> free <a href=\"https:\/\/www.warmy.io\/free-tools\/email-deliverability-test\" target=\"_blank\" rel=\"noopener noreferrer\"><span>email deliverability test<\/span><\/a> which provides information on<span> your current standing.\u00a0<\/span><\/p>\n<p><span>It helps users get data on the following:<\/span><\/p>\n<ul>\n<li><span>Know where your emails land (Inbox, Spam, Promotions tab) across major providers like Gmail, Outlook, and Yahoo! and what percentage lands in which folder.<\/span><\/li>\n<li><span>Know if your sending IP or domain is blacklisted, as this could also trigger SMTP errors and delivery failures. In the event you are indeed listed, <a href=\"https:\/\/www.warmy.io\/blog\/email-domain-ip-blacklist-removal-steps-to-delist-your-ip\/\" target=\"_blank\" rel=\"noopener noreferrer\">follow these steps to delist.<\/a><\/span><\/li>\n<li><span><a href=\"https:\/\/www.warmy.io\/blog\/why-do-you-need-to-configure-spf-dkim-and-dmarc\" target=\"_blank\" rel=\"noopener noreferrer\">SPF, DKIM, DMARC<\/a> verification: Ensure proper authentication to reduce deferrals and enhance sender credibility.<\/span><\/li>\n<\/ul>\n<p>Watch this video to give you an idea of how the <a href=\"https:\/\/www.warmy.io\/free-tools\/email-deliverability-test\" target=\"_blank\" rel=\"noopener noreferrer\">email deliverability test<\/a> is conducted:<\/p>\n<p><iframe width=\"640\" height=\"360\" src=\"https:\/\/www.youtube.com\/embed\/tE5-KqNryaQ\" frameborder=\"0\" allowfullscreen allow=\"accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture; web-share\"><\/iframe><\/p>\n<h2>Conclusion<\/h2>\n<p><span>Ultimately, keep in mind that troubleshooting SMTP Error 552 5.3.4 and similar errors is all part of the process to maintain your email deliverability reputation. <\/span><\/p>\n<p><span>T<\/span><span>hese errors may cause setbacks that affect your business, your outreach with customers, and more. Thus, it\u2019s important, over time, to ensure that such things don\u2019t happen. <\/span><\/p>\n<p><span>This means that you should always keep an eye on your sender reputation, ESP configurations, etc. <\/span><\/p>\n<p><span>Warmy.io gives you the tools to maximize email as a communication channel and avoid any setbacks for your own business.<\/span><\/p>\n<p><span><a href=\"https:\/\/www.warmy.io\/signup\" target=\"_blank\" rel=\"noopener noreferrer\">Sign up for a free trial today<\/a>, or <a href=\"https:\/\/www.warmy.io\/book-a-demo\" target=\"_blank\" rel=\"noopener noreferrer\">book a demo<\/a> where an expert will walk you through how Warmy can transform your email strategy.<\/span><\/p>\n<p>\ud83d\udcdc <strong>Related articles<\/strong>:<\/p>\n<ul>\n<li><span><a href=\"https:\/\/www.warmy.io\/blog\/how-to-fix-smtp-email-error-552-5-1-1-solved\/\" rel=\"noopener\" target=\"_blank\">SMTP Email Error 552 5.1.1 \u2013 How to Resolve [SOLVED]<\/a><\/span><\/li>\n<li><span><a href=\"https:\/\/www.warmy.io\/blog\/how-to-fix-smtp-email-error-552-5-7-0-solved\/\" rel=\"noopener\" target=\"_blank\">SMTP Email Error 552 5.7.0 \u2013 How to Resolve [SOLVED]<\/a><\/span><\/li>\n<li><span><a href=\"https:\/\/www.warmy.io\/blog\/how-to-fix-smtp-email-error-552-5-3-4-solved\/\" rel=\"noopener\" target=\"_blank\">SMTP Email Error 552 5.3.4 \u2013 How to Resolve [SOLVED]<\/a><\/span><\/li>\n<\/ul>\n","protected":false},"excerpt":{"rendered":"<p>In today\u2019s world, communicating without email seems nearly impossible. Email works through transmission via the Simple Mail Transfer Protocol and here\u2019s a quick overview of how it works: When one sends an email, the sender\u2019s email client attempts to establish a connection with the SMTP server responsible for handling outgoing emails.\u00a0 When the connection is [&hellip;]<\/p>\n","protected":false},"author":2,"featured_media":4644,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[104],"tags":[],"class_list":["post-3865","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-email-deliverability"],"acf":[],"lang":"en","translations":{"en":3865},"pll_sync_post":[],"_links":{"self":[{"href":"https:\/\/www.warmy.io\/blog\/wp-json\/wp\/v2\/posts\/3865","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.warmy.io\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.warmy.io\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.warmy.io\/blog\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.warmy.io\/blog\/wp-json\/wp\/v2\/comments?post=3865"}],"version-history":[{"count":1,"href":"https:\/\/www.warmy.io\/blog\/wp-json\/wp\/v2\/posts\/3865\/revisions"}],"predecessor-version":[{"id":5677,"href":"https:\/\/www.warmy.io\/blog\/wp-json\/wp\/v2\/posts\/3865\/revisions\/5677"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.warmy.io\/blog\/wp-json\/wp\/v2\/media\/4644"}],"wp:attachment":[{"href":"https:\/\/www.warmy.io\/blog\/wp-json\/wp\/v2\/media?parent=3865"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.warmy.io\/blog\/wp-json\/wp\/v2\/categories?post=3865"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.warmy.io\/blog\/wp-json\/wp\/v2\/tags?post=3865"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}