Spate of 550-5.7.26 Your email has been blocked" DSNs since a couple of days ago

chrisjj · 3 Nov 2024, 10:09 AM

Sending through the FM SMTP server (no change to settings), the auto-bcc to Gmail is recently often failing with DSN:

550-5.7.26 Your email has been blocked because the sender is unauthenticated. Gmail requires all senders to authenticate with either SPF or DKIM. 550-5.7.26 550-5.7.26 Authentication results: 550-5.7.26 DKIM = did not pass 550-5.7.26 SPF [chrisjj.com] with ip: [103.168.172.197] = did not pass 550-5.7.26 550-5.7.26 For instructions on setting up authentication, go to 550 5.7.26 https://support.google.com/mail/answ...authentication

This despite the fact chrisjj.com gets a pass from three email deliverability checkers.

Any ideas?

3 Nov 2024, 10:09 AM	#1
chrisjj Cornerstone of the Community Join Date: Jul 2003 Posts: 783	Spate of 550-5.7.26 Your email has been blocked" DSNs since a couple of days ago Sending through the FM SMTP server (no change to settings), the auto-bcc to Gmail is recently often failing with DSN: 550-5.7.26 Your email has been blocked because the sender is unauthenticated. Gmail requires all senders to authenticate with either SPF or DKIM. 550-5.7.26 550-5.7.26 Authentication results: 550-5.7.26 DKIM = did not pass 550-5.7.26 SPF [chrisjj.com] with ip: [103.168.172.197] = did not pass 550-5.7.26 550-5.7.26 For instructions on setting up authentication, go to 550 5.7.26 https://support.google.com/mail/answ...authentication This despite the fact chrisjj.com gets a pass from three email deliverability checkers. Any ideas? Last edited by chrisjj : 3 Nov 2024 at 09:56 PM.