Ghosted Profiles

I have a problem with laptops and disappearing profiles on W2K Prof workstations with multiple hardware profiles.
When you go to device manager/hardware profiles, there are blank profiles or the profiles that were previously defined are gone. Can anyone assist me with this error.
Technet says the users are replacing the kernel or ntdetect files with 4.0 versions, but that doesn’t jive with what I see and what my users tell me.
Please reply to jlc@e-lynxx.com