This article was previously published under Q311782
If you are using Fast User Switching to switch between two different users on a portable computer, the Fn+function key combination to toggle the display mode may not work for the second user, or may work only once. The Fn+function key combination that you use varies depending on the manufacturer of the portable computer.
You may experience similar symptoms in the following scenario:
You start a portable computer without a CRT monitor attached. In the properties of the Power Options tool in Control Panel, the When I close the lid of my portable computer setting is set to Do nothing.
You close the lid of the portable computer.
From another computer that is running Microsoft Windows XP with Service Pack 2 (SP2), a Remote Desktop connection to the portable computer is started. The Remote Desktop connection is established, and then logged off.
You open the lid of the portable computer. The LCD screen on the portable computer remains blank.
You connect a CRT monitor to the portable computer, while the portable computer is running. The Windows XP desktop displays on the CRT monitor.
You press the Fn+function key combination to change the display device to the LCD screen.
Nothing happens. The Windows XP desktop still displays on the CRT monitor.
Avoid using the Fn+function key combination when you are logged on as the second user if Fast User Switching is enabled. Or, the first user can log off the computer instead of using the Fast User Switching functionality. Additionally, in the scenario that is previously described, you can leave the lid open on the portable computer to work around the issue.
In some cases, when the second user presses the Fn+function key combination, no display may be active. If this occurs, you must restart the computer.
If you experience the issue where you cannot switch the display to the LCD screen after a Remote Desktop connection session was established and then logged off, restart the computer.
Microsoft has confirmed that this is a problem in the Microsoft products that are listed at the beginning of this article.