I searched the past topics on this but haven't been able to come up with any similar to my installation.
We've migrated to Exchange 2010 from Exchange 2003 and we're about ready to decommission our Exchange 2003 box but......
After upgrading one of our other software packages (telephone server) which was talking fine to the exchange 2003 it has stopped sending our voicemails to our email clients (Outlook 2010). As it turns out none of our other servers regardless of version (2k3 - 2k8R2) can forward mail to the exchange 2010 box. I'm receiving the following message. "Message delivery to the remote domain 'domain.org' failed for the following reason: Unable to bind to the destination server in DNS." with Event ID 4000.
I have been scratching my head on this for days and none of the articles covering this message seem to help. I can telnet to the email server and I get the proper responses. When I do nslookup it appears to be the correct information.
I've even tried to setup the smtpsvc on some test machines to use the exchange 2003 box without success.