I see. Looks like Default apps can't be deleted, but alternate app can be chosen for that function. Correct?

I did try SFC and got the message:
"Windows Resource Protection did not find any...

JohnC,

Thanks for your advice. I will try that. But I think I need to find a tutorial on apps in Win10. I have assumed that the control panel > Programs and Features would show all installed...

After returning from long sleep I find the start menu doesn't work. Also, right clicking on taskbar item has no effect.
When this happens I need to restart :(

Today during restart I got message...