Upgrading to Horde Framework 5.2.14 solved the problem.
Thanks for the tip.
Horde Internal Server Error
I think since update to 0.9.1.1 Davdroid shows me a similar error message. Since I use Horde I don’t think that’s a problem with the caldav server.
Before the update everything works fine an I didn’t change something at the server.
@user1: If you think that a server error message doesn’t indicate a server error, I think there’s nothing I can do for you.
Of course, if there is any plausible hint that the problem is on DAVdroid’s side, I’ll have a look at it.
I downgraded to version 0.9.0.4 and everything works fine.
Some details from the error Horde/sabredav error message:
HORDE [kronolith] SQL QUERY FAILED: SQLSTATE[HY000]: General error: 7 no connection to the server
Maybe you can give me a hint how to look further. Thanks.
@user1 Please ask in the Horde community because this is a Horde error message.