I have an old AMD processor PC, and 3 days bfore i formatted the HDD and (Tried to)reinstalled windows XP pro. I set the boot sequence in the Bios setting and started installing windows. After the first restart, i NOTICED I cannot enter the serial number coz my keyboard is not working. I restarted the computer and i saw the keyboard works in the bios settings. But when windows start loading the keyboard works. I tried chaging the keyboard and reseting the bios settings. Didnt work. This system was working on WIN xP with no trouble. How could this suddenly happen. Am using a USB mouse and a PS2 keyboard. Do u think its a hardware conflict. Does anyone knows how to fix it? Apreciate the helpIs the PS2 port DEFECTIVE with any of the pins missing or is it not plugged in all the WAY? There could be a plastic tab broken off so ANOTHER keyboard can't be plugged in. If so you can remove the tab from the new keyboard plug and get it to go all the way in.

Gizmo73A real PS/2 keyboard in a properly functioning system solves all of this.

You don't have two keyboards plugged in at the same time do you?