I checked in the AppData\Roaming\Thunderbird\Profiles\Mail the Archives.sbd with all the subfolders still there.
But it showed only two profiles for main and local. So, I check on forums for a solution and one direction was to check the profiles in the help/problem solving tab. I am not so experienced in trouble shooting. Also the archive folders with the submap structures are gone. Since then all my emails in my inbox and archive folders have disappeared. Hello, my Thunderbird performed yesterday ,9 November 2020, an automatic update to version 78.4.0 (from 68.12.1).
