When I run the GWXUI app (Windows 10 upgrade app), I see what looks like a web page with no stylesheets applied:
Click image for larger version
Clicking on the links doesn't do anything.

It should look something like this:
Click image for larger version

I can't figure out why this is happening or how to fix it (or even good terms to type into Google). I've tried disabling all EMET mitigations for GWXUI.exe and iexplorer.exe, tried disabling AVAST, and tried resetting Internet Explorer. Nothing has worked so far.

Any ideas? ...or even good search terms for Google? The only thing I can find on this specific issue is a pretty unhelpful page on Reddit.