550 5.4.4: No Route to Destination
The 550 5.4.4 bounce means the sending server cannot find any mail servers for the recipient domain. Learn how to diagnose and fix this routing error.
Published · Last verified · Maintained by TamingDNS
550
5.4.4
No Route to Destination
Very Common
🔢 Enhanced Status Code Breakdown: 5.4.4
| Component | Value | Meaning |
|---|---|---|
| Class | 5 | Permanent failure (Hard bounce) |
| Subject | 4 | Network and routing |
| Detail | 4 | No Route to Destination |
Per RFC 3463 Enhanced Mail System Status Codes. Class (X) = severity, Subject (Y) = category, Detail (Z) = specific condition.
💬 What This Error Means
Your mail server is lost! It tried to deliver the message but couldn't find any 'mail servers' listed for the domain you're sending to. It's like trying to mail a letter to a house that doesn't have a mailbox (or even an address).
Common Causes
- The domain doesn't have any "MX records" (the digital signposts for mail)
- The domain has expired or been taken down
- There's a typo in the domain part of the email address (like @gmal.com instead of @gmail.com)
How to Fix This
- Carefully check the domain (the part after the @) for typos
- Use our Domain Checker to see if the domain actually has working mail servers
- If it's your own domain, check your DNS settings immediately to ensure your MX records are correct
📚 Official Documentation
📋 Real-World Example Messages
These are real bounce message formats you might receive. Paste yours into the Bounce Decoder for instant analysis.
550 5.4.4 Unable to route: recipient domain has no MX record 550 5.4.4 ROUTING.NoMX; MX record for domain doesn't exist
🔗 Related Error Codes
🔧 Related Diagnostic Tools
These tools can help you diagnose and fix this type of bounce:
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