Possibly due to a desktop security program such as Script Logic's Desktop Authority.
That app can make all kinds of changes (depending on how the network tech configures it) to your pc as soon as you log onto the network. Installing specific printers can also be config'd. I can send a user's printjobs to a printer in a different building's printer's (that's really funny)....
We use Desktop Authority and users don't even see their C drive or have access to it...
It can be configured by user name, pc name, OU, etc...the things it can do are basically unlimited. Many of our users hate it for they can't even change their wallpaper.
Do a Cntl-Alt-Del, go to processes and see if you see something running out of the ordinary.
With Desktop Authority, you'll see one of the processes titled DesktopAuthority.exe
Keep us posted....
