Hello,
We're using managesieve to manage the vacation autoresponder.
We have a lot of 'clients' using @gmail.com email addresses and they each get an automatic response whenever they send an email to one of our email addresses.
Everything was working fine until one day, google decided to bounce our vacation messages with error 550 5.7.1 .
The mail log entry looks like this:
Sep 4 09:21:51 ourServer postfix/smtp[506196]: DB6826E001A: to=<someuser@gmail.com>, relay=gmail-smtp-in.l.google.com[142.250.102.27]:25, delay=13, delays=5.1/0/8/0.31, dsn=5.7.1, status=bounced (host gmail-smtp-in.l.google.com[142.250.102.27] said:
550-5.7.1 [<our ip>] 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 https://support.google.com/mail/?p=UnsolicitedMessageError
550 5.7.1 for more information. s14-20020a17090699ce00b00992fef51a60si5752086ejn.525 - gsmtp (in reply to end of DATA command))
Regular messages sent to @gmail.com users are reaching the destination without issues.
I'v talked to google workspace support level 1 and 2 but since they support only google workspace related issues, it didn't help.
We've set up DKIM and SPF records according to their suggestion, so everything is set correctly.
The funny thing is; if using managesieve I set the 'Discard with message' instead of 'Reply with message', the discard message reaches it destination, google marks it as spam and moves it in the Spam folder (which is way better than bouncing and not reaching the recipient mailbox).
So my thoughts are it must be something to do with the header.
I have opened a case at google's support, the ticket is now more than two months old and I never got a response.
Do you guys have any idea on what should I do to fix this issue?
Any help is appreciated.
Kind regards,
Jan