Ok I have a friends Dell computer that she asked me to get running for her. She previously had the computer in a shop and they reinstalled windows for her not using the original Dell discs that came with the computer. Now she gets a pop up that asks to register windows every day. I have the numbers off the side of the computer put there by Dell but everytime I put them in I get a invalid key error. What can I do now???? After 30 days it says I wil no longer be able to use windows.