I run my own CalDAV/CardDAV-server to synchronize all my calendar events and contacts across my devices. Everything was working fine until I upgraded to El Capitan a few days ago.
Now Addressbook can't connect to the CardDAV-server anymore. After I checked the logfiles on my server, I figured out what the problem is: The setup assistant in System Preferences asks for the server address but actually saves a completely different (maybe standard) address, which then of course won't work.
Does someone know how to fix this? Maybe I can change the values via Terminal and change the settings there.
It also seems that these accounts don't sync properly via iCloud, which makes the account working fine on one machine and not working on the other machine. Of course I can't delete the synced account there and make a new one because then it will just move the problem between the machines.