Currently experiencing problems when basic domain users login to their desktops. I have three desktops running Windows Vista Business experiencing the same problem.

Here is the problem:
- User will login to their account as they normally do -- no problems occur before the login process.
- Windows Vista will display the "Welcome" dialog along with spinning orb thing.
- After a few moments, the entire screen will go black. Pressing CTRL+ALT+DEL will not result in a security dialog. There is no way to start explorer or task manager. The system will never unfreeze (as far as I know). I believe I have been able to move around the mouse on the screen, but I do not remember at this time.

Notes:
- An administrative user logging into the system (with Domain Admin privileges) will not experience these problems. This user does not need to be given local admin rights (although I believe Domain Admin's already have them already).
- Enabling / disabling UAC does not affect this problem.
- The system event log does not show any relevant information to this problem. It appears that no information is ever written to it.
- This problem only began recently -- and occurred within a few days on each of the systems. Around that time, IE8 was installed automatically along with other updates via WSUS and Windows Updates.
- System Restore does not appear to help this problem -- despite how it does attempt to undo the most recent Windows Updates.

Temporary solution:
- I disabled three login scripts which are based on the kix32 platform. I disabled these scripts by simply moving the files to another location from their previous location in NETLOGON.
- Systems will work after I have moved these login scripts.
- If I run these login scripts interactively from the users desktop via a command prompt, I experience no problems.
- Guessing that there was a permissions problem, I checked permissions on these scripts and granted access to 'Everyone'. This did not help solve the problem -- I had to disable them again.
- There have been no other major changes made to these systems. There is no reason why these simple login scripts should simply stop working.

Whats wrong with these scripts?

 Code:
--- Example of one of the script files ---
If InGroup("QuickBooks Users")
        Use q: /delete /persistent
        Use q: "\\twinserve\quickbooks"
EndIf