451: Local Processing Error (Temporary)

The 451 SMTP error means the receiving server hit a temporary local error. Learn what causes this and when your email will be retried.

Published · Last verified · Maintained by TamingDNS

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Temporary Failure (Soft Bounce)
SMTP Code
451
Category
Local Processing Error (Temporary)
Frequency
Common

💬 What This Error Means

The receiving server encountered a temporary local error while processing your message. This is usually a transient server issue.

Common Causes

  • Server-side content filter or virus scanner error
  • Temporary database or processing resource issue

How to Fix This

  • Your mail server will retry automatically
  • If it persists beyond 24 hours, the issue may be on the recipient server

📚 Official Documentation

↗ RFC 5321: SMTP

📋 Real-World Example Messages

These are real bounce message formats you might receive. Paste yours into the Bounce Decoder for instant analysis. 

451 Local configuration error, please retry after 1 minute
451 4.3.0 Temporary local problem - please try later

🔗 Related Error Codes

450
Requested Action Not Taken (Temporary)
452
Insufficient Storage (Temporary)
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