SMTP error 552 signifies your email was permanently rejected (5xx) due to issues with its size or content (phpmailer, jenkins). This indicates the message exceeded server size limits or violated content policies.

What are the cases covered in SMTP Error 552?

Common scenarios triggering SMTP Error 552:

1. Oversized Emails: The email, including attachments, exceeds the recipient server's size limits (set to conserve resources and prevent abuse).
2. Policy Violations: The email content violates the recipient server's policies, such as containing spam, malware, or prohibited file types.
3. Problematic Attachments: Large or problematic attachments within the email might trigger this error.
4. Rate Limiting: Some servers use SMTP error 552 to limit email sending rates to prevent server overload.

What’s Causing This SMTP Error 552 In Your Servers?

Potential causes of SMTP Error 552:

• Reduce Message Size: Compress attachments, use file-sharing services for large files, or break content into smaller messages (phpmailer, jenkins).
• Review Content: Ensure email content complies with recipient server policies. Remove or modify anything flagged as spam or malicious.
• Verify Attachment Sizes: Check attachment sizes and consider file-sharing services for large files to avoid exceeding limits.
• Respect Rate Limits: Send emails at a slower rate to comply with recipient server policies.

How to Resolve SMTP Error 552 - Step-by-Step Solution

Reduce Message Size:

• Compress attachments.
• Use file-sharing services for large files.
• Break content into smaller messages (phpmailer, jenkins).

Review Content:

• Ensure content complies with recipient server policies.
• Remove or modify anything flagged as spam or malicious.

Verify Attachment Sizes:

• Check attachment sizes.
• Use file-sharing services for large files to avoid exceeding limits.

Respect Rate Limits:

• Send emails at a slower rate to comply with recipient server policies.

SMTP Error 552 Examples

• "552 5.3.4 Message size exceeds limit. Maximum message size is 10 MB."
• "552 5.7.1 Content blocked due to policy violations. Email flagged as spam."
• "552 5.6.2 Attachment too large. Please use a file-sharing service for large files."
• "552 5.4.3 Rate limit exceeded for sender@example.com. Slow down email sending."

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