[vetiver]

Hey I have an HP pavilion too, just tried plugging my kensington wireless mouse port into the right side usb (right by the power cord, right?) and it worked fine. It may be a problem with Logitech-Vista compatibility or something.

Is the mouse brand new also? My first Kensington only lasted four months before the USB plug became loose or broken or something and would only work in one USB port by holding it with my hand. I doubt you have a cat that likes biting it and rubbing its face against it though, so you shouldn't have durability problems.