I am having a stupid problem that is really making my life hard. Me and my team are trying to release a Computer game tonight and my computer holds allthe source code!! Anyways here's the situation I had Windows XP Home Edition for like a year, and today of all days decided to upgrade to Windows XP Professional and it was going fine until I got to the login screen. After I tried to type in my password I got this error: A problem is preventing windows from accurately checking the license for this computer. ERROR 0x80004005. If anyone could please help me out it would be greatly appreciated. Thank you!!!