keyboard not working after win95 hardware check

the deal is my friend did something to his computer, the one he's buying off of me and im letting him use in the meantime. according to him he plugged the current keyboard into an old computer running windows 95. when he plugged in the keyboard and did a startup he said the comp ran a hardware check on the kb. anyways, when put back in the one i built the keyboard doesnt do anything, the capslock, the numlock, and the light next to it, they all just keep blinking. someone help pls.