I don't think taking ownership of a file will help you to do so with a file you cannot see?
Sorry if this is to simple, but I have to ask. You are looking in Windows/fonts?
It could not have happened by default, but another possibility is they are hidden through language settings.
Over on the left of the opened font folder, select "Font settings" and ensure that the box "Hide fonts based..etc" is unticked.
If the fonts have been moved during the process of your installing, you could try a search for one of the rare fonts, and see where it end up. For example, Cambria??
Fwiw.
Posted quite a lot on the site, but there is an easier way to take ownership of a file or folder. open the attached and run the install reg theirin. This will give you a right click option to Take ownership on the file/folder.
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