Sorry to hear that!
What I can say is that this appears to be a software conflict issue, rather
than hardware related. A relatively small number of users see it. You may
be able to discover what the conflict is through a triage/binary search
procedure using MSCONFIG, if you've got the patience. Start with a
diagnostic boot and add services or startup items 'til the symptom happens.
Anything out of the ordinary in the way of hardware or low level driver type
things? Other security software providing real-time protection?
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