After I applied Windows NT SP6a and MDAC 2.6 SP 2 Refresh, my Outlook 2000 stopped working. When I run it, it asks for User Id, Pwd, and Domain name. After I enter the info, it keeps working indefinitely showing only the Outlook 2000 splash screen. I don't have an unusual number of messages in any of the folders. I tried removing Office 2000, re-installing and it didn't help. I applied Office 2000 SP1a and SP3 with no luck. I have no trouble running Outlook 2000 and seeing my messages on another computer that has NT4 SP6a and "MDAC 2.5". I ran some utilities and saw that Outlook 2000 has a number of files locked and I see it running in Task Manager. However, the number and list of files shown is different on the two computers. I can't roll back to MDAC 2.5, in case MDAC 2.6 is the cause, because dasetup.exe has trouble rolling back. Ideally, I'd prefer to have MDAC 2.6 or higher because it would solve some of our database problems. Any suggestions please.