In all recent versions of Windows(Windows Vista, Windows XP and Windows 7), the OS automatically restarts/reboots after running Windows Update, irrespective of the type of update (manual, automatic, scheduled). This might cause inconvenience if you work on the system at the time of an update.
Any unsaved work will be lost in the auto-restart. The user gets only a prompt, which if left unattended, results in a restart. Windows XP service pack 2 and above have options to apply the updates only when the user restarts the computer (ie. no auto-reboots), but that does not appear to be enforced always.
Also see: how to prevent auto sleep in Windows.
Stop automatic restarts
To prevent such issues, follow the steps below and bid goodbye to automatic restarts for good.
- Run Registry Editor by typing regedit in Start > Run (or into the search box for Vista and above) .
- Go to
- Change the value of NoAutoRebootWithLoggedOnUsers to 1 to disallow auto-reboot. If you need to enable it later, repeat the steps till this one and change the value to 0.
- Exit Registry Editor.
There is also a method to do the same in group policy editor for OSes which have it (namely XP Pro), but for simplicity’s sake, I have written steps which work on all versions.
If you need any help, write a comment below.