Since middle March 2021 we had a bunch of support tickets about calendar synchronisation affecting different mail clients.
After playing find-the-common-thing between all these tickets, it looks to us that it is affecting customers that are using DAV to sync their Calendar and Contacts.
- an Outlook user using CalDavSynchronizer on Outlook
- a Mac user using Outlook configured with CalDav/CardDAV
- a Thunderbird user using some CalDAV/CardDDAV extension
All these started at the same time and looking at SM changelog I find this:
Build 7751 (Mar 22, 2021)
Fixed: Harmonizely connected via CalDAV does not sync fully due to non-standard GUIDs being used.
Fixed: Some appointments do not sync via CalDAV if the requested resource path is URL encoded.
It would match the date these customers started having problems.
I was personnally able to reproduce the issues With outlook+CalDavSynchronizer but had not yet confirmed for Mac mail and Thunderbird.
What I also can tell is that it seems it doesn't affect emClient configured in DAV mode, but it loooks like the only client unaffected so far.
Another observation is that when using Outlook and CalDavSynchroniser, when you create/edit/modify an appointment from Outlook (that get then synced to the server) it seems to loose the "owner" of the calendar event.
When it is able to sync, and when you then check in the webmail the created event, it is like it wasn't owned by the user it says is was created by "" (empty)
Also CalDavSynchroniser then throws exceptions due to 404 on objects:
It's a bit worrying because if our users starting to create or change objects from a caldav synchronized device and it lose the object "owner" on the way, it is going to go in a situation we will need to reassign somehow the objects to their owner....
Pleaes can you take a look at this ASAP ?