Windows Vista and Windows 7 Black Screen on Computer Unlock
Consider the following scenario:
- A Windows Vista or Windows 7 computer is running the “Aero” graphics mode.
- The Windows Vista or Windows 7 computer is subject to additional security restrictions and security software, such as might be the case in the enterprise, or with mandated security settings and software such as DISA or DoD requirements.
- The computer is locked and left undisturbed long enough for the screen to go black, which is 20 minutes with the default power policy of “Balanced”.
- A person unlocks the computer by entering their user credentials.
After the credential are entered the screen goes black, and remains black for as much as 10 minutes or longer. The machine is not “hard-locked”, as periodic disk-drive activity may be noted from the disk-drive indicator light on the computer, if so equipped.
For more information on this issue, including potential causes, workarounds, and resolutions, see: Microsoft KB Article KB2431700.