Profile: dcooneyca

I have upgraded from 3.10 to 3.20 and now two of my three stores do not work properly I get the following message.

The controller for path '/' was not found or does not implement IController.

Thank you for your help.

I am also trying to copy the beauty theme.  I have followed the instructions in this post but I have problems with the featured categories on the main page.  Instead of displaying the text "Featured Categories" it reads "sevenspikes.themes.beauty_red.common.featuredcategories".

What have I missed?