So I have looked HIGH AND LOW and could not find anything. I need help trying to reinstall windows 7. I had to switch motherboards from an old motherboard to a new MSI motherboard. Please read carefully. Because people are saying different things. MY COMPUTER WON'T BOOT WINDOWS 7 and I want to reinstall it so it could work with my new stuff that I have such as my motherboard. MY HARD DRIVE WAS NOT CHANGED. I need to know how to do a reinstall of windows 7. This is a desktop computer btw. I DO NOT HAVE ANY DISK FOR WINDOWS 7 NOR DO I HAVE ANY ACTIVATION KEY. I am very confused on how to make a simple reinstall for the computer so it can work again. PLEASE HELP ASAP. I put on caps to so the main problems. Sorry if you thought I was angry at you guys. Thanks for any help.