Keyboard not recognized by pc

I recently formatted my hard drive and re-installed Windows 2000 Server Edition. Everything was running smoothly on it. However next day i was cleaning my keyboard (it was still connected to my PC which was turned on) and it stopped working. I rebooted the PC and it did not recognize the keyboard. I tried two other keyboards and neither responded. Since the PC is not recognizing a keyboard or mouse I cannot maneuver around to check settings. I tried the original keyboard in another computer and it worked just fine. I don’t know what to do from here. Please help.