So here is the latest scenario. I am setting up a new Exchange 2007 server in an effort to migrate Exchange 2003 users over to it. During the setup of Exchange 2007 we ran into some schema permissions issues, and in an attempt to correct them we tried uninstalling Exchange 2007 and deleted the SMTP connectors that Exchange 2003 needs in order to deliver mail to Exchange 2007.
While working with Microsoft to correct our AD Schema permission errors, the Microsoft Technician gave me a commandlet to run to rebuild the connectors. The problem was the commandlet did not build them correctly. When I migrated my test user over to 2007, it could send outbound mail fine, and could send email to users on 2003, however since all inbound mail flowed through the 2003 server, no mail could go to the new user.
On the Exchange 2007 server I used the mail flow troubleshooter tool, and received the following error:
Mail submission failed: Error message: The SMTP host was not specified
I was able to correct the issue though by doing the following:
- Migrated my test user back to Exchange 2003
- On Exchange 2003, I opened Exchange System Manager
- I navigated to Administrative Groups> Exchange 2003 Server>Routing Groups>Connectors
- I deleted the connector for the Exchange 2003-2007 Server
- I navigated to Administrative Groups> Exchange 2007 Server>Routing Groups>Connectors
- I deleted the connector for the Exchange 2007-2003 Server
- On The Exchange 2007 server, I went to Start > Control Panel> Programs and Features
- I selected Exchange 2007 and clicked Uninstall
- I uninstalled the Hub Transport Role
- I rebooted Exchange 2007
- When it booted back up, I went to Start > Control Panel> Programs and Features
- I selected Exchange 2007 and clicked Change
- I re-installed the Hub Transport Role
- When I did, it provided me with an option to create an SMTP connector with Exchange 2003
- Moved my test user back to Exchange 2007
After that, mail flow was working perfectly! Ever have this problem? How did you fix it? Hit me up in the comments!