554 5.4.6: Routing Loop Detected
The 554 5.4.6 bounce means your email got caught in a routing loop between mail servers. Learn what causes mail loops and how to fix them.
Published · Last verified · Maintained by TamingDNS
554
5.4.6
Routing Loop Detected
Common
🔢 Enhanced Status Code Breakdown: 5.4.6
| Component | Value | Meaning |
|---|---|---|
| Class | 5 | Permanent failure (Hard bounce) |
| Subject | 4 | Network and routing |
| Detail | 6 | Routing Loop Detected |
Per RFC 3463 Enhanced Mail System Status Codes. Class (X) = severity, Subject (Y) = category, Detail (Z) = specific condition.
💬 What This Error Means
Your email is stuck in a 'hall of mirrors.' It got caught in a loop, bouncing back and forth between two servers without ever reaching the recipient. Eventually, the servers noticed the loop and gave up to stop it from going on forever.
Common Causes
- A mistake in the server settings that tells Server A to send to Server B, and Server B to send back to Server A
- A circular chain of email forwarding (e.g., John forwards to Mary, and Mary forwards back to John)
- Conflicting rules in a company's email system that can't decide where the message should go
How to Fix This
- Review mail routing rules and forwarding settings on your server
- Check for circular forwarding chains
- Contact your email administrator to audit mail flow rules
📚 Official Documentation
📋 Real-World Example Messages
These are real bounce message formats you might receive. Paste yours into the Bounce Decoder for instant analysis.
554 5.4.6 Too many hops 554 5.4.6 Hop count exceeded - possible mail loop
🔗 Related Error Codes
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