Problem solved. It was the OpenTasks app.
SOLUTION: In the permissions settings of the OpenTasks app the option “Contacts” (in german “Kontakte”) has to be turned on.
Thanks for your help.
I just purchased DAVdroid from the Google Play Store: it is version 188.8.131.52-gplay
I store my calendar on my personal server. This works fine with Apple’s Calendar.app and Mozilla’s Thunderbird (Lightning). I don’t use CardDAV, only CalDAV.
When I try to setup DAVdroid, I choose “Login with URL and user name”. I set the base URL to the same URL used by Calendar.app (Thunderbird doesn’t seem to support calendar-home-set, so I have to add the calendar name to the URL used by Thunderbird).
I use the same username and password that work fine with Calendar.app and Thunderbird.
DAVdroid then complains that it can’t find any CalDAV configuration on my server. I have pasted the debug logs here: https://paste.fedoraproject.org/paste/kb9R3FwUL6JnR~MYCytbqA
From the logs, it seems to be trying the URL that I provide but failing with a 401 Unauthorized error. I am definitely providing the same username and password that work in my other CalDAV clients (i.e. Calendar.app and Thunderbird) and which also work if I open that URL in Firefox.
Any idea why DAVdroid cannot authenticate? Is there any more information I can provide that would help you to debug this?
Thank you for your help.
Which server do you use? Are there any special characters in username/password?
DAVdroid seems to use Digest authentication (which it must use when both Basic and Digest are available). Maybe the other clients use Basic authentication? Did you check whether your username/password work with Digest authentication? Or maybe you can turn off Digest auth. on the server and use only Basic instead, which provides an equal level of security when used over HTTPS?
@rfc2822 Thank you for the quick response.
There are no special characters in the username or password, just ASCII letters and numbers.
The server only offers Digest authentication. So I can’t turn it off… but that also means that Firefox, Calendar.app and Thunderbird are all using Digest authentication successfully with the same username and password.
I am using kCalDAV: https://kristaps.bsd.lv/kcaldav/
Can you provide a test account so that I can have a look? In this case, please send it to firstname.lastname@example.org
I have set up a test account on my server and e-mailed the details to email@example.com - with any luck, I remembered to encrypt them with your PGP key first…
Seemed to be server problems:
Please keep us up to date about your experience with newer versions of kcaldav.