MusicallyInspired, on 30 March 2016 - 04:38 AM, said:
But it worked FINE before all this! I could write to root C until my heart was content. Something changed.
Do you know what folders need to be owned by what?
I don't know if it's a valid fix, but there's a tool called Windows Repair that can restore permissions to system files. It worked for me when I had such problem, but these automated tools should be handled with caution.
What I've seen from looking at the files is that interface shortcuts such as Desktop and folders related to the Start Menu need to be owned by either SYSTEM or TrustedInstaller (don't remember which). But you need to do more than that to fix them, you need to repair the junctions as well. That's why it may be better to use an automated tool to do the dirty work.
MusicallyInspired, on 30 March 2016 - 04:38 AM, said:
I've never had a problem customizing any other version of Windows (besides ME). I dislike Microsoft's "hands off, you lowly dirty customer you" approach. And everyone's for that matter (game developers, movie studios).
I also dislike it.

Unfortunately the usual tools aren't working in the newer updates. I can't make my gaming box as cool as I want because MS hates us. So I'm not trying anything until the customization tools start to keep up.
That being said, when it comes to core functionality I usually leave it as is because it just works (most of the time).