how do i stop downloading and installing windows 11

Yes, modifying the registry is the only way to stop Windows Update from downloading and installing the Windows 11 upgrade. This article was extremely helpful to me: https://www.howtogeek.com/765377/how-to-block-the-windows-11-update-from-installing-on-windows-10/

It explains the whole process WITH screenshots. It was very simple!

Also, I believe it is important to delete Windows Update Cache. Windows itself says that it is completely safe to delete everything out of the SoftwareDistribution/Download folder. See the following YouTube video and Microsoft forum articles:

https://www.youtube.com/watch?v=tHerbmtWV6o

https://answers.microsoft.com/en-us/windows/forum/all/cwindowssoftwaredistributiondownload-deleting/7121844b-82bb-4a53-ad52-3a93fcfc9ffb

I restarted my computer and ran Windows update and it updated the current version of Windows 10 (21H2) and there's no sign of Windows 11 upgrade notifications. I am super pleased, however, it took WAY too much of my time to figure out this one, simple thing! Windows can be so unintuitive sometimes.

Here is where you can figure out what the latest version of Windows 10 is (this will be important for modifying the registry to update the version of Windows you want to get updates for): https://docs.microsoft.com/en-us/windows/release-health/release-information

Also, you may find it helpful to reset Windows Update. You can do so using Windows Update Troubleshooter: https://support.microsoft.com/en-us/windows/windows-update-troubleshooter-19bc41ca-ad72-ae67-af3c-89ce169755dd

Thank you so much for this! I have applied this entire fix to 2 of my computers and will on others in the home once I login to them another day. One of them managed to get Windows 11 on it without my consent, after a couple days trying it out, I was pulling my hair out. So I just installed a fresh Win 10 on that laptop, instantly applied this regedit fix and there is no mention of Win 11 in the updates menu yet. My other computer has the "your computer doesn't meet the requirements" but I've still done the regedit fix to block it from trying anyways. I am fairly adept with computers so I was confident to try this and it seems to be working so far. I'll edit or post again if Win 11 tries to sneak back in anyways.

Since I may get asked my issue with Win 11, here's the list:

1. Cannot set the taskbar to "Never combine", turning everything to icons without names on them, since I tend to use windows rather than tabs, this makes finding what I need take so much longer.
2. No option to "show all icons on the taskbar" so I have to manually have it show for every, single, new app. I have some apps that require keeping an eye on that icon.
3. Two of my older games ran terrible, but run fine on Win 10. Even after changing every setting possible. These are games I still actively play.
4. Nvidia settings removed all of their color adjustments since Win 11 should be able to adjust those now, but it doesn't, so my eyes hurt without being able to dull the colors. Intense colors bothers my eyes.
5. The start menu, even customizing it as best I could, it's extra steps to get to the app list.
6. Internet Explorer was the only browser that would still open my Router's setup page. It may be an older router but it still 100% works and I will not be contributing to the landfills before necessary.
7. I reinstalled 11 fresh because it was a buggy upgrade, then a buggy rollback, so I rolled forward again, reset PC, and then found out it required internet to setup the computer (there is a work around I found online). I prefer offline setup. This was before fresh installing back to Win 10 today.
8. Can't drag programs to the taskbar from Desktop to create a shortcut, need to find the app in the menu and use that "Pin to Taskbar" method.
9. A few of the points in this list, plus the nightmare of finding the setting you want buried in the new Settings menu, makes for more arm movement to find what I want or do my regular tasks, aggravating my repetitive strain injuries much faster than usual.
10. These devices are to serve the needs of the user, not the needs of the distributor. Windows 10 is also finally hitting it's stride after having a similar awful launch, where I had to find ways to stop it installing over Win 7 for a couple years. Eventually I went forward to 10, when they put all the features back they took out of 7. So some day I may be fine with Win 11 but not while it's a step backwards OS with a new paint job (though you can still old style menus when you dig deep enough).
11. I did not ask for it.

That's what I remember from the past few days, I had already reinstalled Win 10 by the time of writing this so I may have forgotten a thing or two. That's not to say that 11 had no redeeming features. I could see it being a decent OS in time, but it removed too much of what I use / need to make it even tolerable for me.

AdityaP177 your reply is way too scary for non-technical PC users.

If you had read my very recent post, you would see that the situation seems to have been resolved by Microsoft who have changed their Notifications to include an option to stay with Windows 10 v. 21H1 and also to upgrade to Windows 1 v. 21H2 while also advising me that my PC could run Windows 11 - if I want to.

And so far that seems to be working just fine.