Apologies as I made this thread after having useless read all the other threads. I'm having difficulty trying to put 64-bit windows 7 on my desktop. I've already checked and it says it is compatible, however, whenever I get to the window to install it, it says my harddrive isn't compatible and it's unable to install. The odd part is that it has been installed on the harddrive before, and like I said, I've already checked to make sure it is compatible in order to do so. How would one go about getting or even forcing 64-bit onto the computer. At the time of making this, I'm not at home to get the specs for the computer, but I would really like assistance.