Greetings Programs! 
We use NextCloud in a small office for files, but mainly for a shared calendar (or several of these) and shared phone books etc. The NC runs on a shared hosting packageā¦
I just did the upgrade from OC 8.2.2 via NC 9.0 to NC 10.0 and now 10.0.3. The weirdness is that some (not all) shared resources only half work. Example:
We have a public office calendar where things of relevance for the whole office are stored (like xyz is on vacation and things like that). For this I created a special user that has no priviliges but only shares certain calendars and phone books. I also created a few user groups to have some sort of control over who has read-only and who has write access to the resource.
I now no longer have write-access to these shared resources although reading still works fine. When I set a new appointment, only my own calender and one other is shown as an option where I can create itā¦ I also cannot move any of my CEOs appointments - which I should be able to do.
The one calendar (apart from my own) that I still have write access to is one where my write access was granted to me personally (using my user user name) and not via any group. All other calendars are blocked for write access.
Of course I have tried adding my user name to the shared list. This did not do any good. Nor did unsharing and resharing the calendar for write access.
When I log in as another user I can change the entries in the calendars (or create appointments). And these changes show up in everyone elseās displays.
Has anyone seen an effect like this before and and idea of how to get over it?
Best regards,
Chris
Update
I have some additional information to share. Maybe this will help outā¦
I have managed to slightly improve the situation. I logged on as the company (unprivileged) user and disabled all shares in his calenders. I logged off an on again and again set up the shares. I logged off again and logged in under my own username. Now I again had write access to the shared calenders - from within the web interface. I still cannot change or create events from within Thunderbird or using my mobile phone (LG G5, running Android 7 and DAVDroid)ā¦ I can still edit and change events (and tasks btw.) in my own calendar using Thunderbird or my phone, but not in calendars shared with me - and yes, I did make sure that the ācan writeā box was checked when sharing them. 
Note that before I only removed and replaced the part of the share with the write access. This time, I completely unshared the calendar and reshared it.
Basically:
- read access works everywhere
- write access works via web interface
- write access to own calendars and tasks works via Thunderbird and Android phone
- write access to own and shared address books works via Thunderbird and Android phone.
We did have a slight situation with our webspace prior to the problems. I donāt know if there is a connection, so I am adding this info here to be thorough. The NextCloud shares space with our website (different directory and DB however). Our webspace had a script that kinda ran amok, creating countless files with a 12 byte error message in each. That went unnoticed until the disc quota was reached (at 2Ā¹āø files). The described write access problems started at the same time, but I donāt know if there is a connection. Anyways, I removed the script and deleted all the log files, so now we have plenty of room again.
Does anyone have an idea what I can do to normalize things again?
Regards,
Chris