Hi Tex,

Your mouse should be detected by your BIOS when you boot? So, do you get to some sort of selection screen where you chose the OS? if so, is the mouse working when you get that far, and stops when you have actually gone into XP?

Is it a USB mouse, is USB enabled?

Does it work if you boot into safe mode? (USB will probably not be detected)

Can you borrow another mouse and check if the same thing happens? It would be nice if you could get a serial mouse, as that should use a different driver?

Otherwise just try deleting it in your hardware manager and re-boot to see if windows redetects it.

EDIT: Might be totally irrelevant but check the power management properties of the mouse..........don't allow Windows to switch it off.

You might then use the hardware trouble shooter?

Otherwise try re-installing the drivers as suggested.

Good luck