Thinks for the hint.

Unfortunatly for me it was too late. I successfully installed the older version now as recommended but face now two problems:

When I wanted to transfer a map to my GPS it refused to word because of a “wrong language DLL” on mapistall. I reinstalled an older version as recommended. The error remains and comes up as I start Mapinstall. What else can I do?
Found a workaround using the good old Mapsource but I’d prefer to keep using Basecamp.

Next problem I’m facing is when I wanted to recover my data from a recent backup file. It appears that in certain folders only data way before 2019 are reinstalled. I’m not sure though if something got missing when I did the backup or if the problem is related to the now installed Basecamp but I checked with an older backup with same results. Any ideas?

Thanks folks