After you start the computer in diagnostic startup mode, you are prompted to activate Windows Vista even if you have already activated it. If you do not activate Windows Vista again, the system is considered non-genuine. Therefore, Windows Vista runs in reduced functionality mode.

This problem occurs only in diagnostic startup mode. When you restart the computer in normal startup mode, the problem does not occur.

Note: The activation prompt does not necessarily mean that you are using a non-genuine copy of Windows Vista.