Error: SelectedTab cannot be set before the pane has been added to a panes collection (FreshRestart doesn't work, either)

I’m still new to Trados Studio 2021and Windows 10 (installed on my Mac Big Sur using Parallels).

However, I have already encountered the persistent twin messages that say “Error: SelectedTab cannot be set before the pane has been added to a panes connection” when trying to open a file for translation. This prevents me from going into the Editor area.

File > View > Reset Window Layout did not work.

I also ran Freshstart.  I allowed the app to make changes to my device.  However, nothing happened, and the screen that should show file name paths, etc. did not come up.

What should I do?

Do I need to uninstall and reinstall Trados?  

Thank you.

Miki