Sync problem with calendar after provider Update

[A Former User]

I hope you can help me.
I can’t figure it out, if it is a server or a client problem.

I’ve been synchronizing my contacts and calendars with DAVdroid over years.
Now my provider Hetzner.de has updated the Horde software (Version unknown).

And now DAVdroid is reporting a error during the synchronization process.
He synchs my contacts, tasks, and my calender 2 and 3 perfectly and with no problems.
But my main Calendar1 reporting an error:

Server error while listing the server entries

Attached the debug info.
(Just removed my personal stuff)

Don’t know what this message is:
Expected 207 Multi-Status, got 200 OK

Thx for your help!

DEBUG: https://paste.fedoraproject.org/paste/YcetpcbXA1NHfFBFEu70KQ

[rfc2822]

This is a server problem. Please contact Horde support and provide your DAVdroid debug info.

[A Former User]

I’ve fixed the problem.

The problem was caused by old calendar entries.
Clearing the howl calendar made the error disappeared.
So Thread could be closed.

Thx for your answer!