I am in the process of upgrading a 2003 Domain with Exchnage 2003 to a 2008 Domain with Exchange 2007. Here is why I am having my problem...
My external domain name is: abc.com
My internal domain name is: def.ghi.jkl.net
I inherited this company when it was already set up this way. they had on 2003 domain controller with Exchange 2003 installed on the DC.
I installed two new servers with Server 2008 each and made one a DC in the domain and installed Exchange 2007 and DNS on the 2008 DC.
Everything went fine and all servers can see each other and all shares are working properly.
I moved a mailbox from the Exchange 2003 server to the Exchange 2007 server. I am able to receive email but can not send.
I ran the Microsoft Exchange Troubleshooting Assistant on the Exchange 2007 server and I receive an error message under root causes:
Server server2003.abc.com is a remote server to which server Server2007 is trying to send messages but no 'Host' records of server server.abc.com can be obtained from any DNS servers server Server2007 uses. This may be causing message backups in the queue.
Server2008 is resolving Server2003 with the external domaian name of server2003.abc.com, goes outside the network then tries to come back in. We use Postini so we only allow email to come in from outside from Postini so server2003 rejectes the email from server2008
Now I know this leads to the obvious of a DNS issue so I checked DNS.
All DNS records internally are listed under the domain def.ghi.jkl.net and abc.com is not entered anywhere.
There is a mail Connector setup between the two email servers.
Do I need to add the domain abc.com to my internal DNS? If so, how do I do it without messing up the def.ghi.jkl.net internal domain???