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Bounce Decoder: 550 5.1.2

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550 5.1.2 — Bad Destination Domain

The 550 5.1.2 error means the recipient domain has no working mail servers. Learn the causes and how to fix this SMTP bounce.

🔴
Permanent Failure (Hard Bounce)
SMTP Code
550
Enhanced Code
5.1.2
Category
Bad Destination Domain
Frequency
Common

🔢 Enhanced Status Code Breakdown: 5.1.2

Component Value Meaning
Class 5 Permanent failure
Subject 1 Addressing
Detail 2 Bad Destination Domain

Per RFC 3463 Enhanced Mail System Status Codes. Class (X) = severity, Subject (Y) = category, Detail (Z) = specific condition.

💬 What This Error Means

The domain part of the recipient address doesn't have working mail servers, or the domain doesn't exist at all. The email has nowhere to go.

Common Causes

  • The domain has expired or been deleted
  • MX records are missing or misconfigured on the recipient domain
  • Typo in the domain part of the address

How to Fix This

  • Check the domain part of the address for typos
  • Use our Domain Checker to verify the domain has MX records
  • If it's your domain, ensure your MX records are configured correctly

📋 Real-World Example Messages

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

550 5.1.2 Bad destination mailbox address
550 5.1.2 <[email protected]>: Recipient address rejected: Domain not found

📚 Official Documentation

RFC 3463 — Enhanced Status Codes
🔍

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