I have an Exchange 2003 and Exchange 2010 server in co-existence. Currently users whos mailboxes are on the 2010 server can use OWA and ActiveSync. Users with Mailboxes on 2003 can not. When trying to access OWA: 404 - File or directory not found.
When trying to access and ActiveSync connection: An HTTP 401 Unauthorized response was received from the server. This may be the result of invalid credentials or a configuration problem on the Exchange Server
I have installed the patch needed on 2003. http://support2.microsoft.com/?kbid=937031
I have set Windows Integrated Authentication on the Microsoft-Server-ActiveSyn
What to try next?