I found what actually went wrong! When I have right-clicked on the file I haven’t first selected it with a left-click so I’ve edited the permissions on my user folder instead of the key.
I didn’t realize I needed to left-click to select it as it shows a similar indication when I hover…

oh, thank you, I did a crosspost!

It was the ssh key I changed permissions on. I’ve added System and Administrator to have full permission again. When applying the changes it seems to struggle with some files in AppData.
(When I previously tried to install node (not sure if this was before or after) the wizard couldn’t find the file AppData.)

Errors I get now when applying the changes:

At last, it finished and created some new permission inherited from c:\Users\

omgomg that helped, thank you so much.

I ran a troubleshooter on the Windows Update and it didn’t find anything wrong. I have no pending updates either.

I have not done a DISM image repair, I’ll look into that.
I did do, got help doing an SFC scan but it didn’t detect anything odd.

Ohai! I’m exited for this site!