Microsoft refused to validate my windows XP when reinstalling, I decided to acquire the latest version of the inescapable window. it works pretty well, without miracles, but older software like photoshop elements 5 no longer work. Even more annoying, even infuriating, my scanner Lexmark 6570 printer no longer works. The drivers are found. So if you have the hardware and software a bit old but you do not want to throw them, go for Windows 7, you will have fewer surprises.