I'm trying to set up calendar sync for almost a year now. I'm willing to give it one more chance

Right when Nextcloud came out, I thought I’d give it a chance. I ditched Owncloud installed Nextcloud via Webinstaller on my shared host, and started setting everything up. While my Linux client worked perfectly, syncing files was all I could do up to this point.

After many re-installs, changing versions, updating, I can’t just can’t make it to work.
Seems like DavDroid is detecting my calendars, but they don’t sync neither phone to server, nor another way around.

Tried to set it up on Thunderbird, getting a yellow warning icon: “The calendar Mycalendar is momentarily not available.”

Tried to set CalDav URL to:
https://nextcloud.mydomain.com/
https://nextcloud.mydomain.com/remote.php/dav/
https://nextcloud.mydomain.com/remote.php/dav/principals/users/myusername/

Nextcloud 12.0.2 (Webinstaller was at 11, which didn’t work either)
DavDroid 1.6.5
OVH shared host

Could anyone help me debug this? I really like Nextcloud’s concept, but I can’t keep using it without having calendar/tasks/contacts sync.

Use the caldav and carddav addresses given in the sidebar settings of the calendar and contact apps gui. They e.g. also include the username.

Hey, thanks for the reply.

Are you talking about calendar’s sidebar settings on bottom left? If so, I already tried both of those urls, as stated earlier

https://nextcloud.mydomain.com/remote.php/dav/
https://nextcloud.mydomain.com/remote.php/dav/principals/users/myusername/

setting up DavDroid with either of those links gives me the same result:

  • I can see DAVdroid account in Android “Accounts”
  • I can see a list of available calendars
  • I can create a calendar from within DavDroid and that is visible in Nextcloud webapp.
  • I can see all of those calendars in Android’s calendar app in “Calendars to display” page
  • I can see all of them in Android’s calendar app in “Calendars to sync” page
  • when I create a new event, Android’s accounts page says “syncing now” next to my account name, then it becomes “last synced [date]”
  • Unfortunately, the events I created do not appear anywhere

just an idea - have you checked for rights and ownership of your files?

Do you mean files on Android, Linux or Nextcloud instance on the server?

check them on the server… should be your http-user (mostly www-data)

Do you have log files of the server? This way you can see which queries can’t be answered on the server and which files the client expects.

since it’s a shared ovh hosting, I doubt I can get access to fully check logs. It has a ‘statistics’ page, where I can check ‘web’, ‘error’ and ‘ftp’ logs. In this case, the error log doesn’t show anything related to my nextcloud instance, but there is some davdroid activity on the web log. I’ll paste one of the excerpts where Davdroid has some activity. I’m really not sure where to go from here :confused:

111.111.111.11 box.mydomain.com - [28/Aug/2017:06:59:18 +0200] "PROPFIND /remote.php/dav/calendars/myusername/c2a15224-86e6-46e4-8f31-bf5bb9baec5b/ HTTP/1.1" 207 540 "-" "DAVdroid/1.6.5-ose (2017/08/08; dav4android; okhttp3) Android/7.1.2"
111.111.111.11 box.mydomain.com - [28/Aug/2017:06:59:21 +0200] "PUT /remote.php/dav/calendars/myusername/c2a15224-86e6-46e4-8f31-bf5bb9baec5b/9efadc60-4c1e-4295-9985-7b9aa8b1b5e1.ics HTTP/1.1" 503 20 "-" "DAVdroid/1.6.5-ose (2017/08/08; dav4android; okhttp3) Android/7.1.2"
111.111.111.11 box.mydomain.com - [28/Aug/2017:06:59:49 +0200] "PROPFIND /remote.php/dav/calendars/myusername/personal/ HTTP/1.1" 207 512 "-" "DAVdroid/1.6.5-ose (2017/08/08; dav4android; okhttp3) Android/7.1.2"
111.111.111.11 box.mydomain.com - [28/Aug/2017:06:59:53 +0200] "REPORT /remote.php/dav/calendars/myusername/personal/ HTTP/1.1" 503 20 "-" "DAVdroid/1.6.5-ose (2017/08/08; dav4android; okhttp3) Android/7.1.2"
111.111.111.11 box.mydomain.com - [28/Aug/2017:06:59:53 +0200] "PROPFIND /remote.php/dav/calendars/myusername/test-calendar/ HTTP/1.1" 207 517 "-" "DAVdroid/1.6.5-ose (2017/08/08; dav4android; okhttp3) Android/7.1.2"
111.111.111.11 box.mydomain.com - [28/Aug/2017:06:59:54 +0200] "PROPFIND /remote.php/dav/calendars/myusername/personal/ HTTP/1.1" 207 512 "-" "DAVdroid/1.6.5-ose (2017/08/08; dav4android; okhttp3) Android/7.1.2"
111.111.111.11 box.mydomain.com - [28/Aug/2017:06:59:54 +0200] "REPORT /remote.php/dav/calendars/myusername/test-calendar/ HTTP/1.1" 503 20 "-" "DAVdroid/1.6.5-ose (2017/08/08; dav4android; okhttp3) Android/7.1.2"
111.111.111.11 box.mydomain.com - [28/Aug/2017:06:59:54 +0200] "REPORT /remote.php/dav/calendars/myusername/personal/ HTTP/1.1" 503 20 "-" "DAVdroid/1.6.5-ose (2017/08/08; dav4android; okhttp3) Android/7.1.2"
111.111.111.11 box.mydomain.com - [28/Aug/2017:06:59:55 +0200] "PROPFIND /remote.php/dav/calendars/myusername/test-calendar/ HTTP/1.1" 207 517 "-" "DAVdroid/1.6.5-ose (2017/08/08; dav4android; okhttp3) Android/7.1.2"
111.111.111.11 box.mydomain.com - [28/Aug/2017:06:59:55 +0200] "REPORT /remote.php/dav/calendars/myusername/test-calendar/ HTTP/1.1" 503 20 "-" "DAVdroid/1.6.5-ose (2017/08/08; dav4android; okhttp3) Android/7.1.2"
111.111.111.11 box.mydomain.com - [28/Aug/2017:06:59:56 +0200] "PROPFIND /remote.php/dav/calendars/myusername/c2a15224-86e6-46e4-8f31-bf5bb9baec5b/ HTTP/1.1" 207 540 "-" "DAVdroid/1.6.5-ose (2017/08/08; dav4android; okhttp3) Android/7.1.2"
111.111.111.11 box.mydomain.com - [28/Aug/2017:06:59:57 +0200] "PUT /remote.php/dav/calendars/myusername/c2a15224-86e6-46e4-8f31-bf5bb9baec5b/9efadc60-4c1e-4295-9985-7b9aa8b1b5e1.ics HTTP/1.1" 503 20 "-" "DAVdroid/1.6.5-ose (2017/08/08; dav4android; okhttp3) Android/7.1.2"
111.111.111.11 box.mydomain.com - [28/Aug/2017:07:00:55 +0200] "PROPFIND /remote.php/dav/calendars/myusername/personal/ HTTP/1.1" 207 512 "-" "DAVdroid/1.6.5-ose (2017/08/08; dav4android; okhttp3) Android/7.1.2"
111.111.111.11 box.mydomain.com - [28/Aug/2017:07:00:56 +0200] "REPORT /remote.php/dav/calendars/myusername/personal/ HTTP/1.1" 503 20 "-" "DAVdroid/1.6.5-ose (2017/08/08; dav4android; okhttp3) Android/7.1.2"
111.111.111.11 box.mydomain.com - [28/Aug/2017:07:00:57 +0200] "PROPFIND /remote.php/dav/calendars/myusername/test-calendar/ HTTP/1.1" 207 517 "-" "DAVdroid/1.6.5-ose (2017/08/08; dav4android; okhttp3) Android/7.1.2"
111.111.111.11 box.mydomain.com - [28/Aug/2017:07:00:57 +0200] "REPORT /remote.php/dav/calendars/myusername/test-calendar/ HTTP/1.1" 503 20 "-" "DAVdroid/1.6.5-ose (2017/08/08; dav4android; okhttp3) Android/7.1.2"
111.111.111.11 box.mydomain.com - [28/Aug/2017:07:01:01 +0200] "PROPFIND /remote.php/dav/calendars/myusername/personal/ HTTP/1.1" 207 512 "-" "DAVdroid/1.6.5-ose (2017/08/08; dav4android; okhttp3) Android/7.1.2"
111.111.111.11 box.mydomain.com - [28/Aug/2017:07:01:02 +0200] "REPORT /remote.php/dav/calendars/myusername/personal/ HTTP/1.1" 503 20 "-" "DAVdroid/1.6.5-ose (2017/08/08; dav4android; okhttp3) Android/7.1.2"
111.111.111.11 box.mydomain.com - [28/Aug/2017:07:01:02 +0200] "PROPFIND /remote.php/dav/calendars/myusername/test-calendar/ HTTP/1.1" 207 517 "-" "DAVdroid/1.6.5-ose (2017/08/08; dav4android; okhttp3) Android/7.1.2"
111.111.111.11 box.mydomain.com - [28/Aug/2017:07:01:03 +0200] "REPORT /remote.php/dav/calendars/myusername/test-calendar/ HTTP/1.1" 503 20 "-" "DAVdroid/1.6.5-ose (2017/08/08; dav4android; okhttp3) Android/7.1.2"
111.111.111.11 box.mydomain.com - [28/Aug/2017:07:01:03 +0200] "PROPFIND /remote.php/dav/calendars/myusername/c2a15224-86e6-46e4-8f31-bf5bb9baec5b/ HTTP/1.1" 207 540 "-" "DAVdroid/1.6.5-ose (2017/08/08; dav4android; okhttp3) Android/7.1.2"
111.111.111.11 box.mydomain.com - [28/Aug/2017:07:01:09 +0200] "PUT /remote.php/dav/calendars/myusername/c2a15224-86e6-46e4-8f31-bf5bb9baec5b/9efadc60-4c1e-4295-9985-7b9aa8b1b5e1.ics HTTP/1.1" 503 20 "-" "DAVdroid/1.6.5-ose (2017/08/08; dav4android; okhttp3) Android/7.1.2"
111.111.111.11 box.mydomain.com - [28/Aug/2017:07:02:59 +0200] "PROPFIND /remote.php/dav/calendars/myusername/personal/ HTTP/1.1" 207 512 "-" "DAVdroid/1.6.5-ose (2017/08/08; dav4android; okhttp3) Android/7.1.2"
111.111.111.11 box.mydomain.com - [28/Aug/2017:07:03:00 +0200] "REPORT /remote.php/dav/calendars/myusername/personal/ HTTP/1.1" 503 20 "-" "DAVdroid/1.6.5-ose (2017/08/08; dav4android; okhttp3) Android/7.1.2"
111.111.111.11 box.mydomain.com - [28/Aug/2017:07:03:01 +0200] "PROPFIND /remote.php/dav/calendars/myusername/test-calendar/ HTTP/1.1" 207 517 "-" "DAVdroid/1.6.5-ose (2017/08/08; dav4android; okhttp3) Android/7.1.2"
111.111.111.11 box.mydomain.com - [28/Aug/2017:07:03:02 +0200] "REPORT /remote.php/dav/calendars/myusername/test-calendar/ HTTP/1.1" 503 20 "-" "DAVdroid/1.6.5-ose (2017/08/08; dav4android; okhttp3) Android/7.1.2"
111.111.111.11 box.mydomain.com - [28/Aug/2017:07:03:16 +0200] "PROPFIND /remote.php/dav/calendars/myusername/personal/ HTTP/1.1" 207 512 "-" "DAVdroid/1.6.5-ose (2017/08/08; dav4android; okhttp3) Android/7.1.2"
111.111.111.11 box.mydomain.com - [28/Aug/2017:07:03:18 +0200] "REPORT /remote.php/dav/calendars/myusername/personal/ HTTP/1.1" 503 20 "-" "DAVdroid/1.6.5-ose (2017/08/08; dav4android; okhttp3) Android/7.1.2"
111.111.111.11 box.mydomain.com - [28/Aug/2017:07:03:18 +0200] "PROPFIND /remote.php/dav/calendars/myusername/test-calendar/ HTTP/1.1" 207 517 "-" "DAVdroid/1.6.5-ose (2017/08/08; dav4android; okhttp3) Android/7.1.2"
111.111.111.11 box.mydomain.com - [28/Aug/2017:07:03:19 +0200] "REPORT /remote.php/dav/calendars/myusername/test-calendar/ HTTP/1.1" 503 20 "-" "DAVdroid/1.6.5-ose (2017/08/08; dav4android; okhttp3) Android/7.1.2"
111.111.111.11 box.mydomain.com - [28/Aug/2017:07:03:20 +0200] "PROPFIND /remote.php/dav/calendars/myusername/c2a15224-86e6-46e4-8f31-bf5bb9baec5b/ HTTP/1.1" 207 540 "-" "DAVdroid/1.6.5-ose (2017/08/08; dav4android; okhttp3) Android/7.1.2"
111.111.111.11 box.mydomain.com - [28/Aug/2017:07:03:21 +0200] "PUT /remote.php/dav/calendars/myusername/c2a15224-86e6-46e4-8f31-bf5bb9baec5b/9efadc60-4c1e-4295-9985-7b9aa8b1b5e1.ics HTTP/1.1" 503 20 "-" "DAVdroid/1.6.5-ose (2017/08/08; dav4android; okhttp3) Android/7.1.2"
111.111.111.11 box.mydomain.com - [28/Aug/2017:07:07:04 +0200] "PROPFIND /remote.php/dav/calendars/myusername/personal/ HTTP/1.1" 207 512 "-" "DAVdroid/1.6.5-ose (2017/08/08; dav4android; okhttp3) Android/7.1.2"
111.111.111.11 box.mydomain.com - [28/Aug/2017:07:07:05 +0200] "REPORT /remote.php/dav/calendars/myusername/personal/ HTTP/1.1" 503 20 "-" "DAVdroid/1.6.5-ose (2017/08/08; dav4android; okhttp3) Android/7.1.2"
111.111.111.11 box.mydomain.com - [28/Aug/2017:07:07:06 +0200] "PROPFIND /remote.php/dav/calendars/myusername/test-calendar/ HTTP/1.1" 207 517 "-" "DAVdroid/1.6.5-ose (2017/08/08; dav4android; okhttp3) Android/7.1.2"
111.111.111.11 box.mydomain.com - [28/Aug/2017:07:07:07 +0200] "REPORT /remote.php/dav/calendars/myusername/test-calendar/ HTTP/1.1" 503 20 "-" "DAVdroid/1.6.5-ose (2017/08/08; dav4android; okhttp3) Android/7.1.2"
111.111.111.11 box.mydomain.com - [28/Aug/2017:07:07:34 +0200] "PROPFIND /remote.php/dav/calendars/myusername/personal/ HTTP/1.1" 207 512 "-" "DAVdroid/1.6.5-ose (2017/08/08; dav4android; okhttp3) Android/7.1.2"
111.111.111.11 box.mydomain.com - [28/Aug/2017:07:07:36 +0200] "REPORT /remote.php/dav/calendars/myusername/personal/ HTTP/1.1" 503 20 "-" "DAVdroid/1.6.5-ose (2017/08/08; dav4android; okhttp3) Android/7.1.2"
111.111.111.11 box.mydomain.com - [28/Aug/2017:07:07:36 +0200] "PROPFIND /remote.php/dav/calendars/myusername/test-calendar/ HTTP/1.1" 207 517 "-" "DAVdroid/1.6.5-ose (2017/08/08; dav4android; okhttp3) Android/7.1.2"
111.111.111.11 box.mydomain.com - [28/Aug/2017:07:07:37 +0200] "REPORT /remote.php/dav/calendars/myusername/test-calendar/ HTTP/1.1" 503 20 "-" "DAVdroid/1.6.5-ose (2017/08/08; dav4android; okhttp3) Android/7.1.2"
111.111.111.11 box.mydomain.com - [28/Aug/2017:07:07:38 +0200] "PROPFIND /remote.php/dav/calendars/myusername/c2a15224-86e6-46e4-8f31-bf5bb9baec5b/ HTTP/1.1" 207 540 "-" "DAVdroid/1.6.5-ose (2017/08/08; dav4android; okhttp3) Android/7.1.2"
111.111.111.11 box.mydomain.com - [28/Aug/2017:07:07:39 +0200] "PUT /remote.php/dav/calendars/myusername/c2a15224-86e6-46e4-8f31-bf5bb9baec5b/9efadc60-4c1e-4295-9985-7b9aa8b1b5e1.ics HTTP/1.1" 503 20 "-" "DAVdroid/1.6.5-ose (2017/08/08; dav4android; okhttp3) Android/7.1.2"
111.111.111.11 box.mydomain.com - [28/Aug/2017:07:17:06 +0200] "PROPFIND /remote.php/dav/calendars/myusername/personal/ HTTP/1.1" 207 512 "-" "DAVdroid/1.6.5-ose (2017/08/08; dav4android; okhttp3) Android/7.1.2"
111.111.111.11 box.mydomain.com - [28/Aug/2017:07:17:06 +0200] "PROPFIND /remote.php/dav/calendars/myusername/personal/ HTTP/1.1" 207 512 "-" "DAVdroid/1.6.5-ose (2017/08/08; dav4android; okhttp3) Android/7.1.2"
111.111.111.11 box.mydomain.com - [28/Aug/2017:07:17:11 +0200] "REPORT /remote.php/dav/calendars/myusername/personal/ HTTP/1.1" 503 20 "-" "DAVdroid/1.6.5-ose (2017/08/08; dav4android; okhttp3) Android/7.1.2"
111.111.111.11 box.mydomain.com - [28/Aug/2017:07:17:11 +0200] "REPORT /remote.php/dav/calendars/myusername/personal/ HTTP/1.1" 503 20 "-" "DAVdroid/1.6.5-ose (2017/08/08; dav4android; okhttp3) Android/7.1.2"
111.111.111.11 box.mydomain.com - [28/Aug/2017:07:17:11 +0200] "PROPFIND /remote.php/dav/calendars/myusername/test-calendar/ HTTP/1.1" 207 517 "-" "DAVdroid/1.6.5-ose (2017/08/08; dav4android; okhttp3) Android/7.1.2"
111.111.111.11 box.mydomain.com - [28/Aug/2017:07:17:11 +0200] "PROPFIND /remote.php/dav/calendars/myusername/test-calendar/ HTTP/1.1" 207 517 "-" "DAVdroid/1.6.5-ose (2017/08/08; dav4android; okhttp3) Android/7.1.2"
111.111.111.11 box.mydomain.com - [28/Aug/2017:07:17:12 +0200] "REPORT /remote.php/dav/calendars/myusername/test-calendar/ HTTP/1.1" 503 20 "-" "DAVdroid/1.6.5-ose (2017/08/08; dav4android; okhttp3) Android/7.1.2"
111.111.111.11 box.mydomain.com - [28/Aug/2017:07:17:12 +0200] "REPORT /remote.php/dav/calendars/myusername/test-calendar/ HTTP/1.1" 503 20 "-" "DAVdroid/1.6.5-ose (2017/08/08; dav4android; okhttp3) Android/7.1.2"
111.111.111.11 box.mydomain.com - [28/Aug/2017:07:17:12 +0200] "PROPFIND /remote.php/dav/calendars/myusername/c2a15224-86e6-46e4-8f31-bf5bb9baec5b/ HTTP/1.1" 207 540 "-" "DAVdroid/1.6.5-ose (2017/08/08; dav4android; okhttp3) Android/7.1.2"
111.111.111.11 box.mydomain.com - [28/Aug/2017:07:17:14 +0200] "PUT /remote.php/dav/calendars/myusername/c2a15224-86e6-46e4-8f31-bf5bb9baec5b/9efadc60-4c1e-4295-9985-7b9aa8b1b5e1.ics HTTP/1.1" 503 20 "-" "DAVdroid/1.6.5-ose (2017/08/08; dav4android; okhttp3) Android/7.1.2"
111.111.111.11 box.mydomain.com - [28/Aug/2017:07:33:19 +0200] "PROPFIND /remote.php/dav/calendars/myusername/personal/ HTTP/1.1" 207 512 "-" "DAVdroid/1.6.5-ose (2017/08/08; dav4android; okhttp3) Android/7.1.2"
111.111.111.11 box.mydomain.com - [28/Aug/2017:07:33:20 +0200] "REPORT /remote.php/dav/calendars/myusername/personal/ HTTP/1.1" 503 20 "-" "DAVdroid/1.6.5-ose (2017/08/08; dav4android; okhttp3) Android/7.1.2"
111.111.111.11 box.mydomain.com - [28/Aug/2017:07:33:20 +0200] "PROPFIND /remote.php/dav/calendars/myusername/test-calendar/ HTTP/1.1" 207 517 "-" "DAVdroid/1.6.5-ose (2017/08/08; dav4android; okhttp3) Android/7.1.2"
111.111.111.11 box.mydomain.com - [28/Aug/2017:07:33:21 +0200] "REPORT /remote.php/dav/calendars/myusername/test-calendar/ HTTP/1.1" 503 20 "-" "DAVdroid/1.6.5-ose (2017/08/08; dav4android; okhttp3) Android/7.1.2"
111.111.111.11 box.mydomain.com - [28/Aug/2017:07:34:04 +0200] "PROPFIND /remote.php/dav/calendars/myusername/personal/ HTTP/1.1" 207 512 "-" "DAVdroid/1.6.5-ose (2017/08/08; dav4android; okhttp3) Android/7.1.2"
111.111.111.11 box.mydomain.com - [28/Aug/2017:07:34:05 +0200] "REPORT /remote.php/dav/calendars/myusername/personal/ HTTP/1.1" 503 20 "-" "DAVdroid/1.6.5-ose (2017/08/08; dav4android; okhttp3) Android/7.1.2"
111.111.111.11 box.mydomain.com - [28/Aug/2017:07:34:06 +0200] "PROPFIND /remote.php/dav/calendars/myusername/test-calendar/ HTTP/1.1" 207 517 "-" "DAVdroid/1.6.5-ose (2017/08/08; dav4android; okhttp3) Android/7.1.2"
111.111.111.11 box.mydomain.com - [28/Aug/2017:07:34:07 +0200] "REPORT /remote.php/dav/calendars/myusername/test-calendar/ HTTP/1.1" 503 20 "-" "DAVdroid/1.6.5-ose (2017/08/08; dav4android; okhttp3) Android/7.1.2"
111.111.111.11 box.mydomain.com - [28/Aug/2017:07:34:07 +0200] "PROPFIND /remote.php/dav/calendars/myusername/c2a15224-86e6-46e4-8f31-bf5bb9baec5b/ HTTP/1.1" 207 540 "-" "DAVdroid/1.6.5-ose (2017/08/08; dav4android; okhttp3) Android/7.1.2"
111.111.111.11 box.mydomain.com - [28/Aug/2017:07:34:09 +0200] "PUT /remote.php/dav/calendars/myusername/c2a15224-86e6-46e4-8f31-bf5bb9baec5b/9efadc60-4c1e-4295-9985-7b9aa8b1b5e1.ics HTTP/1.1" 503 20 "-" "DAVdroid/1.6.5-ose (2017/08/08; dav4android; okhttp3) Android/7.1.2"
111.111.111.11 box.mydomain.com - [28/Aug/2017:08:05:36 +0200] "PROPFIND /remote.php/dav/calendars/myusername/personal/ HTTP/1.1" 207 512 "-" "DAVdroid/1.6.5-ose (2017/08/08; dav4android; okhttp3) Android/7.1.2"
111.111.111.11 box.mydomain.com - [28/Aug/2017:08:05:37 +0200] "REPORT /remote.php/dav/calendars/myusername/personal/ HTTP/1.1" 503 20 "-" "DAVdroid/1.6.5-ose (2017/08/08; dav4android; okhttp3) Android/7.1.2"
111.111.111.11 box.mydomain.com - [28/Aug/2017:08:05:37 +0200] "PROPFIND /remote.php/dav/calendars/myusername/test-calendar/ HTTP/1.1" 207 517 "-" "DAVdroid/1.6.5-ose (2017/08/08; dav4android; okhttp3) Android/7.1.2"
111.111.111.11 box.mydomain.com - [28/Aug/2017:08:05:38 +0200] "REPORT /remote.php/dav/calendars/myusername/test-calendar/ HTTP/1.1" 503 20 "-" "DAVdroid/1.6.5-ose (2017/08/08; dav4android; okhttp3) Android/7.1.2"
111.111.111.11 box.mydomain.com - [28/Aug/2017:08:09:14 +0200] "PROPFIND /remote.php/dav/calendars/myusername/personal/ HTTP/1.1" 207 512 "-" "DAVdroid/1.6.5-ose (2017/08/08; dav4android; okhttp3) Android/7.1.2"
111.111.111.11 box.mydomain.com - [28/Aug/2017:08:09:15 +0200] "REPORT /remote.php/dav/calendars/myusername/personal/ HTTP/1.1" 503 20 "-" "DAVdroid/1.6.5-ose (2017/08/08; dav4android; okhttp3) Android/7.1.2"
111.111.111.11 box.mydomain.com - [28/Aug/2017:08:09:16 +0200] "PROPFIND /remote.php/dav/calendars/myusername/test-calendar/ HTTP/1.1" 207 517 "-" "DAVdroid/1.6.5-ose (2017/08/08; dav4android; okhttp3) Android/7.1.2"
111.111.111.11 box.mydomain.com - [28/Aug/2017:08:09:17 +0200] "REPORT /remote.php/dav/calendars/myusername/test-calendar/ HTTP/1.1" 503 20 "-" "DAVdroid/1.6.5-ose (2017/08/08; dav4android; okhttp3) Android/7.1.2"
111.111.111.11 box.mydomain.com - [28/Aug/2017:08:09:18 +0200] "PROPFIND /remote.php/dav/calendars/myusername/c2a15224-86e6-46e4-8f31-bf5bb9baec5b/ HTTP/1.1" 207 540 "-" "DAVdroid/1.6.5-ose (2017/08/08; dav4android; okhttp3) Android/7.1.2"
111.111.111.11 box.mydomain.com - [28/Aug/2017:08:09:19 +0200] "PUT /remote.php/dav/calendars/myusername/c2a15224-86e6-46e4-8f31-bf5bb9baec5b/9efadc60-4c1e-4295-9985-7b9aa8b1b5e1.ics HTTP/1.1" 503 20 "-" "DAVdroid/1.6.5-ose (2017/08/08; dav4android; okhttp3) Android/7.1.2"

PUT and REPORT get 5xx errors, can you get server error logfiles?