I assume it's a laptop. Just go back over there and physically remove the keyboard. Is it a Compaq, perchance? My aunt had a Compaq that needed its keyboard replaced for some odd reason or another. I can't quite recall what the symptom was, but I do remember it being odd.
It's a Dell, and I'm not sure I want to do that. I think he's already a tiny bit irritated that I wasn't able to help him, and I think he'd be wary of my removing the keyboard from the laptop.
Strange that there's no way to disable it...