I'm on Windows 7 build 7601 x64, and I've tried everything to patch my uxtheme.dll, themeservice.dll, themeui.dll with different patchers – like Universal Theme Patcher – but nothing helps.
I am restoring the original files with
sfc /scannow
and try patching again, but it doesn't change. When I try to activate a custom theme, it opens the default Aero theme.