we are building a new system, and to get it up and running, we would like to use a disc we have here for windows 7. it came with the refurbished computer we bought my son a couple of years back. it says "For use with refurbished machines only" on the disc. now, we do NOT want to do this for keeps, it will allow us to fire the system up and get it running for a month (we get paid monthly, and buying components will take more that we want to spend). and the machine that it belongs to will be retired at that time. so we would use the product key that came with it. so the obvious question is will it work? if not, could we (again, TEMPORARILY), just use the hard drive from his old machine? our goal is to have this running in time for Christmas. and we ALL know what a money madhouse Christmas brings with it.