When you attempt to log off, restart, or shut down Windows XP, your display may flash, but your computer doesn't log off, restart, or shut down.
This behavior will occur because some versions of Norton Antivirus 2003 use a startup program, ccApp.exe, that needs updating.
To resolve this issue, use Symantec LiveUpdate to update your Symantec Common Client program and your Norton AntiVirus program.
To workaround this behavior, if Fast User Switching is enabled:
1. Press Start and Log Off.
2. Press Switch User.
3. Press Turn off <ComputerName>
4. Press Turn Off or press Log Off.