Contacts don't work

I am using owncloud 8.1 stable one a raspberry pi 2 with resbian in my home network with an external HDD with the user folder on it.
For some quite now I have some troubles with my contacts. I cannot create, edit or delete contacts in my owncloud. I mostly edited then on my android with with the Card dav sync app but even on my owncloud homepage directly it doesn't work. I can only watch them.
File sync, to do list and calender sync just works fine over local network and over the Internet.
I am happy for ever help or link to a useful documentation. When there is information I should provide please tell me.

Please move to a current version of ownCloud (e.g. 9.0.8 or 9.1.4) as there won't be any fixes or support for the old calendar / contacts app if the issue is caused by them.

Oh OK. Can you provide me a link to a upgrade documentation from 8.1 to 9.x. Or do you recommend a clean install?


-> Search box on the top right

-> upgrade

Skipping major releases is not supported.

I installed owncloud manuel with the owncloud-8.1.0.tar.bz2. So I have to install 8.2, 9.0 and then 9.1 to get to the final version. Is this right?

Yes, that is correct. A correct upgrade from 8.1.0 to 9.1.4 would be:

8.1.0 -> latest 8.1.x -> latest 8.2.x -> latest 9.0.x -> latest 9.1.x

All previous releases are available at

Would you recommend doing this? Or should I make a clean install of the latest version. Because the user dir is on the external drive I shouldn't have much problem restoring my data.
All this afford just to get support for system with an issue. A clean install would be faster and the issue would be gone also.

Sure, a clean install would be faster but you would loose all sharing stuff (like shared links). Furthermore contacts and calendars are saved in the database, not in the datadir and needs to be migrated between 8.2 and 9.0. So you can't just use a database dump from 8.1 within 9.1.

I have no shared content. I use my owncloud to sync /backup my few documents and as a Google calender and contacts replacement. So I could export my contacts, calender and to do list as a file, make a clean install with 9.x and just import my contacts, calender and to do list again. So not much to worry about I guess. What do you say?