Here is another strange oddity that I had to fix recently.
I had a user running Windows XP with SP3 that upon log in the desktop items would all come up ok but when the user clicked on anything to open any application the pc would freeze. At first the mouse would still be able to move but after attempting to click on anything else a few times the pc would lock up completely. The only way to recover was to do a hard reboot. I tracked this back to 4 windows udpates that were installed the day the symptoms started. What fixed this issue for me was to disable all Antivirus software and use System Restore to go back to the begining of the week. After the reboot completed and System Restore was successful the machine logged in and all was good again. I am still looking into which of the 4 updates caused this issue.
If you have any suggestions please let me know. As always this may not have been the only way to fix this problem but "ItFixed it for me"
For more "ItFixed it for Me"Articles click here.