While trying to determine why windows xp would not recognize a new external hard drive (already have two working perfectly) I somehow disabled the Plug and Play function. I restarted and it told me there was a plug and play error, I fit F1 to skip and XP loaded up but only displaying in 4 bit which cannot be adjusted and any external hard drives cannot be detected (mouse and keyboard can). I tried a system restore to a time well before my f'up and that did not work. I tried running sfc/scannow and it wants me to use the boot CD which is long since lost. Any help would be greatly appreciated.