As with other verions of Microsoft Windows, such as Windows XP, Vista, 7, 8, you may find Microsoft Windows Server 2012 and the Windows Server 2012 Essentials edition rebooting the system at inopportune times for updates. You can temporarily delay the shutdown by issuing the command
net stop "windows update"at a command prompt. Note: you need to open an admin command prompt to do so, which you can do by moving the mouse pointer to the lower, left-hand corner of the screen, then right-clicking on the Start button when it appears and choosing Command Prompt (Admin). But that wil only postpone the reboot, because Windows will later restart the service on its own, even if you don't reboot. You can determine if it has restarted by reissuing the command. You will see a message "The Windows Update service is not started", if it isn't running.
You can pemanently disable the automatic restart by changing the
group policy for
the system by running
gpedit.msc, which you can run by
issuing the command
gpedit at a command prompt or by
right-clicking on the Start button, choosing Run and
gpedit.msc and hitting Enter. When
the Local Group Policy Editor window opens, navigate to
Computer Configuration > Administrative Templates >
Windows Components > Windows Update.
In the right pane of the window, you will see "No auto-restart with logged on
users for scheduled automatic updates installations". Change the setting
from "Not Configured" to "Enabled".
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