If you’re like me and leave your computer all the time and have Windows updates set to auto download and install. I’m sure you saw this message before. “Windows recently downloaded and installed an important security update to help protect your computer. This update required an automatic restart.” Hopefully you saved any important things you were working on, If not your S.O.L. Or if your in front of your computer after an install you get the nag message pop-up window with a countdown that wants to reboot your computer in 15 seconds. Now you can stop that with a quick Registry edit. ( Always backup your Registry before making any changes.)
Step 1. Click Start, then Run. Then type regedit and press Enter.
Step 2. With the Registry Editor opened, click and expand HKEY_LOCAL_MACHINE\SOFTWARE\Policies and finally Microsoft\Windows.
Right-click on Windows and select New\Key with your left mouse.
Type WindowsUpdate and press Enter. This will create a new folder. Now right-click on that folder and create another new key, this one named AU, and press Enter. AU stands for Auto Update.
Turn to the right-hand pane, where the entry reads (Default); right-click in the empty space and select New DWORD Value. Enter the string NoAutoRebootWithLoggedOnUsers, and press Enter.
Now double-click that entry and change the Value Data to a 1, with the Base button of Hexadecimal selected.
Click on File > Exit, after which the Registry autosaves. Now reboot, and you won’t need to worry about your computer auto rebooting after installing an update.