Recently one of my friends gave me her Sony Vaio VGNSR520G laptop with Windows 7 on it. But I had issues with the hard drive (system repair loop) and I had to reset it to its factory settings, which included Windows XP and not Windows 7. I'm thinking of getting Windows 7 again, but I'm wondering if I would be able to use the activation code/product key from the Windows 7 before the factory reset. Is this possible?