Explain the problems
1) After downloading the update, the installation not completed, and a message like this appears
windows 11 update install error - 0x800f081f
You may have disabled Windows protection to install a program or game, and you are unable to re-enable the protection.
2) When you open the Windows protection box, a black screen appears.
Solve the problems
One step will solve most Windows problems such as the update problem, the blue screen, the missing drivers, the security center problem, etc..
From here choose your version of Windows: Microsoft download center
Then download Windows 11 Installation Assistant
Do not worry, this method will not delete your files or settings, it will only update Windows and fix problems while keeping everything.
Now accept to download in the traditional way
The download and checking for updates process will take some time.
During the installation process, agree to restart the device
Finally, the problem with Windows Update and Security Center has been resolved
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