what happened is the computer detected the mouse and sence windows didnt have the vendor/product ids in its driver database, it loaded its own generic mouse driver before you installed the one it should be using. i find you need to install the usb drivers before the usb device most of the time. what i think you need to do is attach the mouse and open up the device manager. remove the mouse from the system and all its related entries, like hid devicees linked to it. you may actually have to purge the drivers as well (in vista they give you a checkbox to actually delete the files from the windows folder). once you do that disconnect the mouse, uninstall the drivers and reboot. when it comes back up install the drivers, then plug in your mouse. this makes sure the windows driver database has the proper entries.