I just received my first gmail bounced email with this content:
Code:
550-5.7.1 [x.x.x.x 12] Our system has detected that this message is
550-5.7.1 likely unsolicited mail. To reduce the amount of spam sent to Gmail,
550-5.7.1 this message has been blocked. Please visit
550-5.7.1 http://support.google.com/mail/bin/answer.py?hl=en&answer=188131 for
550 5.7.1 more information. fm4si16129174wib.68 - gsmtp
It's thread subscription notifying user about new posts in thread, and AFAIK, all other emails passed so far.
I checked SPF, there is TXT (no SPF) record in DNS and it's so for years. Is there possibility is a fluke, or there could be further problems? And what to do in case further mails get stopped?