Windows explorer crashing and restarting

I was a victim of a trojan this morning which started my Windows explorer crashing and restarting every 5 or 10 seconds. My virus checker caught the trojan and I deleted it at the time. I have run a number of virus checkers with no flags showing up. I have also run AdAware, Spybot, and several registry checkers. I also copied an “Explorer.exe” from an unaffected computer and substituted it into the Windows folder. Nothing has cured the problem. I am running XP with SP2 installed. I would appreciate any assistance that may be offered.