Thanks for the reply.
The problem goes back I think to drivers for my nvidia gts2 ti graphics card which was always blamed for the crash by the xp 'recovered from' screen ! I have since replaced it with an ATI card and removed all references to nvidia I could find. BTW it was while scanning the registry for nvidia that I discovered the file.

Are you using xp and if so is there anything in you folder ?

Obviously the problem is unusual