below i have a message header from an email sent from one user to another in our organization. Both users reside on the same server but in different mailboxes.
Looking at the log it looks like it was passed around servers a few times before coming to rest at the correct mailstore. what could cause this sort of routing issue? Everything else seems to be working without issue.
Received: from INTERNAL-EXCHSRV.internaldomain.local (192.168.1.12) by
INTERNAL-MAILSRV.internaldomain.local (192.168.1.33) with Microsoft SMTP
Server (TLS) id 15.1.466.34 via Mailbox Transport; Mon, 26 Sep 2016 11:29:52
+0100
Received: from INTERNAL-MAILSRV.internaldomain.local (192.168.1.33) by
INTERNAL-EXCHSRV.internaldomain.local (192.168.1.12) with Microsoft SMTP
Server (TLS) id 15.0.1210.3; Mon, 26 Sep 2016 11:29:52 +0100
Received: from INTERNAL-MAILSRV.internaldomain.local ([::1]) by
INTERNAL-MAILSRV.internaldomain.local ([::1]) with mapi id 15.01.0466.034; Mon,
26 Sep 2016 11:29:52 +0100
in short 2016 got the message from the mailbox server
2016 routed the email directly to 2013 to put it in the shadow redundancy
2013 routed it back to 2016 since the mailbox is on 2016
2016 delivered the message