....Computer Dialog Box Is Displayed

Thanks to Clutch for this one:

SYMPTOMS
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.

CAUSE
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.

RESOLUTION
A supported fix is now available from Microsoft, but it is only intended to correct the problem described in this article and should be applied only to systems experiencing this specific problem. This fix may receive additional testing at a later time, to further ensure product quality. Therefore, if you are not severely affected by this problem, Microsoft recommends that you wait for the next Windows 2000 service pack that contains this fix.

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