I recently had Windows Vista and my Hard Drive crashed so I installed a new one and reloaded all the original drivers and programs from the recovery disc. I purchased a Windows 7 upgrade and installed it on my laptop and my Desktop which is a 64 Bit system. It seemed to have loaded correctly but noticed yesterday that I got a message that I needed to activate Windows. So I entered the Product Key # and it kept saying that I needed to re-enter or buy a new program. I can't understand why it keeps saying it when I do have the product key. I never got the message on Vista so what is the system not recognizing ? I woud hate to either re-format my system and reload the Vista program and then upgrade again or have to buy another Windows 7 program. Is there an easier way ?