Task Manager issue - XP Home SP3

This PC has the taskmgr.exe file in the system32 folder, and the task manager has not been turned off in the registry (Windows\CurrentVersion\Policies). When I hit CTRL+ALT+DEL, nothing happens. I get the hour glass for about 2 seconds, and that's it. No error, no task manager, nothing. I copied a known functional taskmgr.exe file from a different PC, and got the same result: nada. The same thing happens if I double-click on the file: nothing. I have scanned for malware and found the system to be basically clean; just some MyWeb type stuff (CursorMania), and not much of that. Ideas? Thoughts? Suggestions?

 

Thanks! I'll give it a look-see tomorrow!
:-D