SMTP Error 552:

What does it mean? And How to resolve this error.

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Error Description

SMTP error 552 is a permanent or "5xx" error code returned by a mail server to indicate that the server has encountered issues with the size or content of an email message, leading to its rejection. This error signifies that the email message exceeds the server's size limits or violates its content policies.

What's Causing This Error?

SMTP error 552 can be caused by several reasons, including:

  • Message size exceeds limits: The email message, including attachments, is larger than the size limits set by the recipient server. Servers often impose limits to conserve resources and prevent abuse.
  • Content policy violations: The email message contains content that violates the recipient server's policies, such as spam, malware, or prohibited file types.
  • Attachment issues: Large or problematic attachments within the email may trigger this error.
  • Rate limiting: Some servers may use SMTP error 552 to limit the rate at which a sender can send emails to prevent overloading the server.

How to fix SMTP Error 552?

  • Reduce message size: If the email message is too large, consider reducing its size by compressing attachments or using file-sharing services for large files. Alternatively, break the content into smaller, manageable messages.
  • Review content: Ensure that the email message content complies with the recipient server's policies. Remove or modify any content that may be flagged as spam or malicious.
  • Verify attachment sizes: Check the sizes of attachments within the email and consider using file-sharing services for large files to avoid triggering size limits.
  • Respect rate limits: If rate limiting is the issue, consider sending emails at a slower rate to comply with the recipient server's policies.

SMTP Error Examples

Example 1: "552 5.3.4 Message size exceeds limit. Maximum message size is 10 MB."

Example 2: "552 5.7.1 Content blocked due to policy violations. Email flagged as spam."

Example 3: "552 5.6.2 Attachment too large. Please use a file-sharing service for large files."

Example 4: "552 5.4.3 Rate limit exceeded for Slow down email sending."

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