About a month ago I started noticing problems with my numpad's zero key. I have a PC, so its a full out keyboard, no Fn key required. The zero key seemed to be working some of the time, but not others. I first noticed it in microsoft excell, but then also started noticing it carried over to other programs, like my web browser and a few others. The zero key would sometimes function and sometimes not. By that I mean if I opened the program at 3 PM, the zero key might not work at all, but 6 hours later it would. This only occurs in some programs - in others it still worked 100% of the time. If I hit numlock, the insert key still functioned 100% of the time, even when the zero key did not. As a last resort, I figured that maybe it was just an issue with an old keyboard. So I went out and bought a new top of the line one and since day 1, I'm having the same problem.. so it can't be that. I really like using my numpad for numbers and tend to go to it a lot, so this lack of the zero key is really upsetting me. I can't imagine why just the one key would function on and off. Normally I don't restart my computer very often, just leaving it on. So the functionality of the key has nothing to do with restarting and then all of a suddon it works. It'll just go in and out randomly. When it does work, every key press produces a zero - so its total functionality is on and off, not 'works every other press' kind of thing. Could it be a virus? Or what? I'm so confused and googling and posting on other sites has gotten me nothing. Please help!