After installing 23.0.12 on the server my Android devices (Version 3.24.2) tells me ‘Die Serverversion wird nicht mehr untertützt …’
What’s the reason and what I’ve to do in order to solve the problem.
Thank you!
Well, your Nextcloud server is very outdated and no longer supported: Maintenance and Release Schedule · nextcloud/server Wiki · GitHub
If you are hosting your Nextcloud server yourself: Updatem If your server is managed by some hoster you can either ask them to update (or switch to a hoster that acts responsible and not careless like this). 
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