Ah, you ran spybot?
I also have a lot of problems with these trojans/spyware/scriptshit which mess up NT systems. And my users are not even Administrators!
If i give them admin rights they try to install kazaa, which is one big piece of spyware, and needs other spyware bots to function.
Also the program ad-aware is good in detecting bots and trojans. Check also for TSR programs, which startup scripts pointers reside in the registry...
Enough horror stories, back to SGI