>>>>Did you figure the pattern? Are the problems reproducible?
>>>>
>>>
>>>No, and no. The only things 'alive' at exit are SDT, my error logger, and a top level form. One user may get it once in a month. Another gets hit every day. Give the bad boy new hardware and fresh software - same result. I'm almost sure it's an operational thing, but why it rears its head at shutdown is the mystery. No reported operational problems from anyone, just the Blue Screens.
>>
>>Did you try already re-installing executable with all support libraries? Is it possible another VFP version is hanging around somewhere?
>
>Brand new computer out of the box exhibited the problem the first week in service.

I agree with Sergey, that plain-Jane VFP should not be capable of BSODing your machines - it's basically sandboxed in its runtime. I'd suspect a driver or hardware problem.

Is it possible that although you gave a user a brand new computer, s/he continues to use their favourite USB mouse or other input device? This would fit in with your earlier suspicion, HIDUSB (Human Interface Device/USB). If that mouse were bad ...

Since you have 2 machines exhibiting problems, do they have *anything* in common? Sometimes, what they have in common may not be obvious. For example, the two machines may be different models, but they may both be HP/Compaq, and running HP/Compaq "help center" (or equivalent) software.

Or perhaps, the same type of AV software, that none of your other machines are running. Or it may even be a unique combination of things e.g. AV + computer make.

Another left-field idea - is either problem location subject to poor-quality electrical power?