The domain after the @ does not exist or has no mail server, so the message cannot be routed.
Hard bounce · permanent
Common causes
- Typo in the domain (yahooo.com, gmail.co)
- The domain expired or was never registered
- The domain has no MX record and no A record
How to fix it
- Correct the domain spelling
- Run an MX lookup on the domain to see whether it accepts email
- Remove addresses at dead domains from your lists
MX CheckerRun the right check for your domain or paste the full bounce message for a precise explanation.
Open MX Checker →Frequently asked questions
How do I know if a domain can receive email?
It needs MX records pointing to reachable mail servers. Use the MX Lookup tool to check.