Here is my issue: I Installed exchange server on Server 2003. When I open AD users & Computers it does NOT have any of the Exchange tabs in a user profile. I install SP1 and try to open ADU&C and get the following error: MMC could not create snap-in MMC could not create snap-in. The snap-in might not have been installed correctly. Name: Active Directory Users and Computers CLSID: {E355E838-1C2E-11D0-8C3700C04FD8FE93} I downloaded a reinstall of AD Users and Computers MMC and it restores the ADU&C MMC to pre Exchange condition. When I rerun Exchange SP1 I get the error above. Does anyone have any thoughts on this? Is there a MMC reinstaller for Exchange 2007? Thanks PhilJK

You should not be using the exchange tabs in ADUC to manage 2007 mailboxes, use EMC or shell. I believe the general idea is that ADUC would be on your desktop, not your exchange 07 server.

In my test environment, I have Exchange 2007 on a DC, and dsa.msc does in fact work properly to administer user accounts (for non-Exchange features). But of course I agree with Knightly - Exchange 2007 101 is dont use ADUC to manage Exchange Server.

Yes, while I am on the fast track to 2007 I am aware of EMC and am using it as my Exchange management,but without ADUC it makescreating users and mailboxes a long drawn out process.Is there a way to reinstall the MMC files? Thanks PhilJK

adminpak.msi which can be found on the windows cd will install ADUC.