Cant change default app settings

dalchina said:

Ok, try this.
Download and install FileTypesMan (free).
Run it, scroll down to html and check the entry matches with what you have in Settings, Choose default applications by file type.
Leave it running.

Assuming it does, now change the browser allocated to html using Settings.

Now click once in FiletypesMan window to focus it, then f5 to refresh. Scroll down to HTML and see if your change is reflected there.
If not, it hasn't been written to your registry.

Are you running as a standard user or as admin?

Changes in settings do not appear in FileTypesMan, and my account is an administrator account.

Ok, sounds like a permissions error or a corrupted user account.
Suggest trying with a new user for test purposes.

You might be in luck if you get Tweaking.com's free repair tool, and, observing its cautious approach, use registry permission repairs. Uncheck any repairs you don't need. You may find other possibly relevant repairs when you look.

dalchina said:

Ok, sounds like a permissions error or a corrupted user account.
Suggest trying with a new user for test purposes.

You might be in luck if you get Tweaking.com's free repair tool, and, observing its cautious approach, use registry permission repairs. Uncheck any repairs you don't need. You may find other possibly relevant repairs when you look.

It didn't help.

Also, it occurred to me a few hours ago that this may be a case of thread-hijacking. (It started as an attempt at giving additional information.)