Have an XP box here that boots to windows desktop but shows nothing but the wallpaper image.

CAD brings up task manager but explorer wont run, gives a "Windows cannot find explorer" error.

All I can do with it is cmd and task manager.

Tried a few things from what I found online but nothing has worked so far, LKGC and safe mode do the same. Copied explorer.exe from another XP box but no joy.

Any ideas? Really don't want to format this one!

As a side note it recently had trojan.vundo cleaned using the Symantec removal tool.