Long shot, but is there any AV installed that may be interfering?
Logitech Unifying Receiver? I ask because I have one plugged into just about every PC I own. I haven't had any issues upgrading with them connected? Keyboards, trackballs, touchpad, no mice though.
rpo, I, too, like Kerry, have the Unifying Receiver plugged in, and have no issues with the mouse. I even use it between my desktop and laptop. Not doubting for a minute what you say is true. Maybe if you un-pair the mouse and re-pair it, that might straighten things out. Or a different USB 2.0 port.