Email to subdomains not being delivered to Mailboxes.
Posted on 2006-10-30
I work for a small organisation and I'm currently in the process of centralising
it's email system. I'm doing this using Exchange 2003 server in a front / end back topology.
I'm hoping to have remote users access email via OWA and RPC over HTTP.
We're running Exchange Service Pack 2 on all servers.
Mail for the central office gets delivered to "email@example.com". This has been working fine.
What I'm aiming to do is get email for "firstname.lastname@example.org" through to "email@example.com"
all delivered centrally. I created a fake subdomain called "test.company.com" along with fake users
and mail for this subdomain gets through to the correct mailboxes.
However, I'm in the process of converting our first "real" site to the central system and no
emails are getting delivered. I've made the changes to the relevant subdomain's MX record so email
gets sent to our central exchange server.
When I ping mail.site1.company.com - it resolves to the correct IP. I have also set up
monitoring on our ISA Server (2004, SP2) and can see the SMTP connections being initiated and closed
again when I send through an email to site1.company...i.e. following the same pattern as email
that gets successfully delivered.
I have created user accounts and mailboxes in A.D. with the correct email addresses
for users at site1. I was of the understanding that from Exchange SP1 and later, as long as
there were matching email fields in A.D.U.C. for a particular user, then email should get delivered to
the proper mailbox. However this is not working for "site1".
Things I've tried so far to troubleshoot:
- Checked IMF's Quarantine folder. The missing emails are not getting flagged as spam.
- Have turned off recipient filtering and restarted all SMTP Virtual servers.
To complicate things a little- I've also been in the process of performing a "swing migration" from one
Back end Exchange server to another. However- I don't think this is to blame as all mail for
"company.com" and "test.company.com" is still doing what it should. The only thing that remains
in the swing migration is to uninstall Exchange from the old server- but I'm holding off a little
as there are users that haven't been re-directed to the new server yet.
Also- the following bounce just arrived (I've been using an external web account to send email in):
A message that you sent could not be delivered to one or more of its
recipients. This is a permanent error. The following address(es) failed:
SMTP error from remote mail server after RCPT TO:<firstname.lastname@example.org>:
host mail.site1.wf.catholic.edu.au [XX.XX.XX.XX]: <---- CORRECT IP for this subdomain's MX entry.
550 5.7.1 Unable to relay for email@example.com
------ This is a copy of the message, including all the headers. ------
Any help with this would be hugely appreciated- I've been telling our remote users how many headaches
our centralised system will solve!