451
SMTP
451 Local Error
The requested action was aborted due to a local error in processing. The server encountered an internal issue that prevented it from completing the command.
Bu Kodu Gördüğünüzde
When the receiving server hits an internal error such as a database failure, DNS lookup timeout, or anti-spam filter processing error.
Nasıl düzeltilir
Retry the message later. If you control the server, check its logs for the specific error — common causes include DNS resolution failures, disk I/O errors, or database connectivity issues.