If the Unlock Computer dialog box is being displayed, a computer that is running Windows 2000 may not respond correctly to a shutdown request such as a remote request by using Shutdown.exe. Instead, the user that is currently logged on may be logged off, and the computer will appear to remain operational. However, further shutdown requests may generate a "Shutdown already in progress" error message. Note that this symptom does not occur if the "Computer Locked" message is being displayed.
The shutdown functions set Graphical Identification and Authentication (GINA) logoff/shutdown flags, but they are overwritten with the result of the Unlock Computer dialog box.
To resolve this problem, obtain the latest service pack for Windows 2000. For additional information, click the following article number to view the article in theMicrosoft Knowledge Base:
260910 How to Obtain the Latest Windows 2000 Service Pack
The English version of this fix should have the following file attributes or later:
Microsoft has confirmed that this is a problem in the Microsoft products that are listed at the beginning of this article. This problem was first corrected in Windows 2000 Service Pack 3.
This problem is most evident when the CTRL+ALT+DELETE (CAD) secure attention sequence (SAS) has been disabled by group policy. In this case, when the computer is locked, the Unlock Computer dialog box is displayed immediately. With CAD enabled, the "Computer Locked" notice is displayed first, until CTRL+ALT+DELETE (the SAS) is pressed.
This is also the case when a password-protected screensaver is interrupted to display the Unlock Computer dialog box, but not if the screensaver itself is running (in which case shutdown occurs normally).
If the CAD SAS is not disabled, there is less chance of a locked workstation being in the "Unlock Computer" stage, as it times out after two minutes.
For additional information about how to obtain a hotfix for Windows 2000 Datacenter Server, click the article number below to view the article in the Microsoft Knowledge Base:
265173 The Datacenter Program and Windows 2000 Datacenter Server Product
For additional information about how to install multiple hotfixes with only one reboot, click the article number below to view the article in the Microsoft Knowledge Base:
296861 Use QChain.exe to Install Multiple Hotfixes with One Reboot
For additional information about how to install Windows 2000 and Windows 2000 hotfixes at the same time, click the article number below to view the article in the Microsoft Knowledge Base:
249149 Installing Microsoft Windows 2000 and Windows 2000 Hotfixes