When I send a message though postfix to clients who have an inhouse exchange server the message never arrives. The strangest thing is it is being delivered as postfix responds with a
250 queued for delivery. Their system administrator can't find the problem so that is not very helpful.
- Did you guys ever had such an issue and what can be done to counter this?
- Any common pitfalls that may apply?
- Or maybe someone has some tips I can give the administrator?
P.s. This issue only happens with inhouse exchange servers.
May 14 00:50:42 mail postfix/smtp: 25CC31DE9F: to=<email@example.com>, relay=mailcleaner.24dns.nl[184.108.40.206]:25, delay=21, delays=0/0/21/0.31, dsn=2.0.0, status=sent (250 OK id=1Uc1YK-00007S-EB)