I sent an email today from BSUPERIOR SYSTEM LTD. but it got flagged as spam and I got “Mail delivery failed: returning message to sender” error. I received an automatic email response which is copy/pasted below.
I contacted my host to check if my domain name is blacklisted. Hopefully, blacklist wasn’t the issue. The problem was simple and the mail delivery failure was due to including my website name in email signature. It’s interesting that some mail servers block email if the domain name is included in the email signature. Anyhow, if you get the same issue as mine, you could remove all URLs from your email including the ones in your email signature. And then try again!
Removing website name from email signature is not professional. As an employee of a company, it’s a good practice to mention our company info in the email. I tried to find some workarounds but no luck. But if anyone knows better solutions, please feel free to share it in the comment section.
This message was created automatically by mail delivery software. A message that you sent could not be delivered to one or more of its recipients. This is a permanent error. The following address(es) failed: email@example.com host mail.example.com [18.104.22.168] SMTP error from remote mail server after end of data: 554 rejected due to spam URL in content