Just erase the drive, not the partition. If already inside a partition, of course can't repartition the disk.
View attachment 761022 View attachment 761021
I got it working! Thanks, toggling the drive in stead of the partition made it all work. Weird the default setting is to display a partition with an identical name as the drive that needs to be formatted. I guess I overdid the trust I had in Apple logic and ease of use.
A new problem has come up, although just reformating the drive once again will solve that I'd prefer a solution that involves a mouseclick or two: I accept double verification during installation. That means a code is sent to my mini when I try to download something from the App Store. That is somewhat inconvenient when I am downloading something on my iPad while on the road where I have no access to the Mini where the challenge is sent... Suggestions?