Visual Studio not installing extensions, even when all instances are closed

I am trying to install an extension from the Visual Studio 2022 Manage Extension window.

It says I have to close all Visual Studio windows, which I did, but it is still not installing.

Solution

I fixed this the bad way

I basically just reinstalled Windows (I would not recommend you to do this, you should always search for a different solution first). I backed everything up, of course.

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