I have just purchased an optical Microsoft mouse.
It works fine some of the time but regularly for no reason
the pointer jumps oof the screen or jumps to the top left
hand corner of the screen.
I have a Mercer notebook running Windows 200 Proffessional
and the mouse has a USB interface. I have tried a
different optical mouse with PS2 interface but it is also
the same.

Then I also get an error message everytime I open Explorer
or any explorer releted window that say "not a valid date.
I have run the latest virus software but found nothing.
Any assistance will be appreciated.