Ok, found something myself here: https://github.com/owncloud/apps/issues/687. Seems like Owncloud is not really good at dealing with some kind of either corrupted, or just “different” .ics imports. So on the owncloud user page I downloaded the not working calendar as .ics file, deleted the owncloud calendar, created a new calendar with the same name, imported the ics file. Seems like everything works now.
415 when creating calendar
I have problems on my Huawei P8. Android is 6.0. When I try to create a calendar - hit CREATE - I have this error appears.
at.bitfire.dav4android.exeption.Http Exeption 415 Unsupported Media Type. I have tried all but noting. Pls advise.0_1501783268676_debug.txt
This is not a DAVdroid problem.
It seems like your server (which one?) doesn’t support extended
MKCOL. Please use your server’s Web interface / other administration facility to create calendars and just synchronize them with DAVdroid.
I used the WebDAV server of Synology. i Could find this kind of setting extended MKCOL