[Blizzard596]

This is on a Sony Vaio laptop and no USB mouse will work on it. Other things like printers work fine, so I know the USB ports are fine, but I'm guessing there's some kind of driver problem with the mouse. The built-in trackpad also works fine. It's only USB mice that don't work.
Is there a way to reinstall XP's drivers without reinstalling everything else?

[Alvin.C]

Hello,

Does the device manager show that the USB mouse is working properly? If not, what does it say?

Also, have you tried re-installing the driver for the device manually?

[Blizzard596]

Well I resolved the problem, but here's the details for reference.

When plugging in the USB mouse, instead of automatically installing like normally, Windows would display the driver install dialog, etc. which would ultimately result in a "data is invalid" error (whatever that means).

Device Manager would show that the drivers were not installed, but was otherwise detecting the mouse.

I finally checked Device Manager on another PC to see which driver files were being used for the mouse and "hid-compliant" devices and copied those files (found in system32 and system32\drivers) to the problem PC, overwriting the originals and that fixed everything.