Disable the automatic reboot after a Windows update

One of the most frustrating aspects of Microsoft Windows is the automatic reboot after an important update. It is especially infuriating when you left the PC with a big download or a lengthy task ongoing and you return to find the login screen and your download/task interrupted.

Eventually, on the latest Windows versions, Microsoft implemented a prompt window that ask you if you want to delay the reboot:

Microsoft Windows - delay update
But often it is not enough since it doesn’t offer the option to postpone the reboot indefinitely, but only for a specified time between 10 minutes and 4 hours, and more importantly it stays up only for a limited time and then, if it doesn’t get any input (that it may happen if you already left the PC), it takes the initiative to reboot the PC.

To prevent the automatic reboot after a Windows update, open the Registry Editor (go to “Start” -> “Run“/”Search” and input “regedit“) and navigate to:
HKEY_LOCAL_MACHINE SOFTWARE -> Policies -> Microsoft Windows -> WindowsUpdate -> AU.
and change the value of “NoAutoRebootWithLoggedOnUsers” to 1; if the setting doesn’t exist, create a new 32-bit DWORD value with that name.

Registry Editor - NoAutoRebootWithLoggedOnUsers

If you have the Professional, Ultimate and other upper-tier versions of Windows, you can change the same setting using the “Group Policy Editor”. Open it (go to “Start” -> “Run“/”Search” and input “gpedit.msc“) and go to:
Computer Configuration -> Administrative Templates > Windows Components > Windows Update
and change the setting for “No auto-restart for scheduled Automatic Updates installations“.

Group Policy Editor - No auto restart-for scheduled Automatic Updates installations

The above location is for Microsoft Windows Vista and Microsoft Windows 7; if you still use Microsoft Windows XP the location is
Local Computer Policy > Computer Configuration > Administrative Templates > Windows Components > Windows Update