Server Hangs at " Applying Computer Settings" on SBS 2003 R2/HP ML

I have followed some solution for the problem that I am facing but it seems ours is a little different. Tonigh, the system seems to just stop, without any errors or events in the event log. When you shut down the machine and restart then it will just sit for hours on end without getting to a logon screen. I have restarted in Safe Mode and disabled many of the services and restarted it again and then it boots up and I am able to logon and restart the services and everything seems to work fine. But after sometime it will lock up again. Can anyone please tell me how to solve this issue? Thanks.

It seems to me like it might be related to Exchange maintenance routines that might be running at night only. I was thinking if your backup is overlapping these routines and causing this problem. You could try to temporarily disable the nightly server backup and see if the problem persists. It can also be your antivirus software which might be scanning Exchange folders. You may also want to exclude those folders from any real time or scheduled scans. .

Exclude from scans: (assuming these are installed on C:)

C:\Program Files\Microsoft Windows Small Business
Server\Networking\POP3\Incoming mail
C:\Program Files\exchsrvr

I will try to make the adjustments and see if that clears it up. I will also try to rate this Merv after a couple of days to see if that resolves the issue. But it is the most logical thing I have heard yet. Thanks for the reply.