You know, this issue is all over the web and with all the Creative solutions out there, the one that should be there, the OFF SWITCH, still doesnt exist. How about putting that in an auto update? Tons of posts, each with solutions more complex than the last, on an operating system that has no off switch.
Only way to stop this, if you are not a programmer or coder, is to go into
settings
update and security
advanced options
Receive updates for other Microsoft products when you update Windows, turned OFF
make sure all switches below Update options are turned OFF
Make sure Update notifications is turned ON
Now at least windows will ask if you want to download updates. Then (supposedly, I haven't done it yet) you can choose to install them right now or not.
Once you have installed them, some installs may force an immediate update or may need one and you can choose to update later, but you are once again committed to Microsoft's control over your reboot.
Now, where it should be, back to Settings
Change Active Hours
You can set it to an 18 hour window where it will not restart all by itself, so you only have a 6 hour window where Microsoft can restart on its own, losing any unsaved data in any open programs or files you may have up and running.
Here is where the off switch should be.
A simple switch, like the one that is there to turn on and off Automatically adjust active hours, could be under it that says
TURN OFF AUTOMATIC RESTART
I liked auto updates and auto install while I was working during the day. Add a nag pop up that says, "Installed Updates - computer must be restarted for them to take effect. Restart Now?" and really go full on customer service and give it a drop down where you can choose when along with a "No, do not remind me to restart again"
FIX THIS. Powershell scripting, registry edits and the other fixes on the web are BS even for those who do know how to implement coding changes into their machines. I guess when enough people lose critical data or royally screw up their computers trying to make changes to their registry's maybe you will fix this. Or maybe you will charge a high tech support fee to fix it. Keep those stock prices rising.