I added an Exchange 2007 server to our Exchange 2003 environment to play around with it (doh!). Now I have some users that cannot acces email. When they open outlook they are prompted for a username and password.
also, on the Exchange 2003 servers I am seeing different events that all have the same basic error:
"The Domain Controller xxxx is running (Unknown Operating System) (Unknown Service Pack). DSAccess requires that Domain Controllers that run Windows 2000 have at least Service Pack 3 installed. "
The specified domain control is actually running Server 2003 with Service Pack 3. Attempts to login to the specified Domain Controller console fail.
Any ideas on which direction I should go to get users back in to email, and correct the DC issue?