You keep wondering why Windows XP upgrade to Service Pack 2 doesn't want to continue, here's how to fix it.

• Open the Command Prompt, type the following:
  cd /d %windir%\inf
  ren oem*.inf oem*.old
  ren oem*.pnf oem*.old1

• Go to Start -> run -> type %windir%\inf
• Copy the file INFCACHE.1 to desktop as backup
• Delete INFCACHE.1 from C:\Windows\inf
• Close all windows and reboot to safe mode
• Start the installation of SP2 and it should go fine.