I'm having trouble adding programs that weren't installed (released as just the program exe) to the "open with" list. They show up in the "choose another app" window, but that takes extra clicks to...

Managed to get that Desktop icon to show back up by deleting the "ThisPCPolicy" keys in both
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OK. Maybe it carried over a setting when I upgraded from Windows 7. Any idea how I can get it back?

I'm talking about in the main window, though. There was an icon for the Desktop there until I ran the "remove all folders" .reg file, and the "Restore All" one didn't bring it back with the rest.

I ran the "remove all" .reg file (yes, it was the 60-bit version), and while it removed them from the This PC folder, it also removed them from the User folder. SO I ran the Restore All .reg file...