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Bounce Decoder: 550 5.4.7

SPF, DKIM, DMARC, FCrDNS, Blacklists & Inbox Prediction

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550 5.4.7 — Delivery Time Expired

The 5.4.7 bounce means the message expiry time was exceeded before delivery. Learn the difference from 4.4.7 and what to do.

🔴
Permanent Failure (Hard Bounce)
SMTP Code
550
Enhanced Code
5.4.7
Category
Delivery Time Expired
Frequency
Common

🔢 Enhanced Status Code Breakdown: 5.4.7

Component Value Meaning
Class 5 Permanent failure
Subject 4 Network and routing
Detail 7 Delivery Time Expired

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

💬 What This Error Means

The maximum time allowed for delivering this message was explicitly exceeded. Unlike 4.4.7 (queue expiry), this indicates the message had an expiry header or the sender\'s configuration imposed a delivery deadline.

Common Causes

  • Message had an explicit expiry time that was reached before delivery
  • Sending server configured with a very short delivery window
  • The recipient server was unreachable for the entire delivery window

How to Fix This

  • Check if your email system has a message expiry setting that is too short
  • Verify the recipient domain is reachable
  • Try resending manually

📋 Real-World Example Messages

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

550 5.4.7 Message expired - unable to deliver

🔗 Related Error Codes

421 4.4.7
Message Expired in Queue
550 5.4.4
No Route to Destination

📚 Official Documentation

↗ RFC 3463 — Enhanced Status Codes
🔍

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