If your XP computer won't boot and you get an error message that says "Windows could not start because of a hardware disk configuration problem," there are several different causes and methods for fixing the problem. Even worse, if you try to use the XP installation CD to repair Windows, the Setup program doesn't detect your current installation of Windows so you can't do a repair.  For tips on tracking down the cause of this problem and getting Windows to boot again, see KB article 314477 at: http://support.microsoft.com/default.aspx?scid=kb;en-us;314477