Created attachment 124414 [details] The log when starting Korganizer SUMMARY The Korganizer is 5.9.3, not 5.9.2 as specified in the bug report, since that version was not present in the enumeration. Since mid-august, korganizer/akonadi stopped synchronizing (both ways) my remote caldav calendar (nextcloud). STEPS TO REPRODUCE 1 1. Launch Korganizer 2. Create a task or event 3. That task/event is never synchronized to the remote server STEPS TO REPRODUCE 2 1. Launch Korganizer 1. Create a task or event with the web calendar on the remote nextcloud server 2. Check that the task/event is correctly saved with another remote client (ex: Etar on Android) 3. Launch Korganizer and wait a few days 3. That remote tasks and events are never synchronized from the remote server anymore EXPECTED RESULT Synchronization should work both ways. SOFTWARE/OS VERSIONS Windows: macOS: Linux version: Debian Buster (10.2), kernel 5.2.17 KDE Plasma Version: 5.14.5 KDE Frameworks Version: 5.54.0 Qt Version: 5.11.3 ADDITIONAL INFORMATION Check the attachment to see the log when starting Korganizer. This bug is major since the tasks and events are only stored in one computer. If a crash should occur, and if akonadi just decide to clear the cached events/tasks (I speak from experience ; you can search for the same kind of bug from 2013), the data will be LOST. In my opinion, this is even borderline critical, since this on the edge of data loss.
Same with me. To investigate further, I've setup a virtualbox with the same version of kubuntu as the one where the problem occurs and connected the korganizer (5.13.3) calendar with the same instance of nextcloud. This synced fine. Conclusion: The problem causing entry is not on the nextcloud side. Then I tried "akonadictl restart" and got this: parse error from icalcomponent_new_from_string. string= "<?xml version=\"1.0\" encoding=\"utf-8\"?>\n<d:error xmlns:d=\"DAV:\" xmlns:s=\"http://sabredav.org/ns\">\n <s:exception>Sabre\\DAV\\Exception\\NotFound</s:exception>\n <s:message>Calendar object not found</s:message>\n</d:error>\n" org.kde.pim.davresource: DavGroupwareResource::onItemFetched: Failed to parse item data. "https://xxxxxx.free-dyn_dns.de/remote.php/dav/calendars/Admin/personal/1598174372.R271.ics" These messages are also in .xsession-errors. I tried to locate some of the contents of the error messages on my system with "find", but to no success. It looks like a parser can't deal correctly with a task entry, calendar item or even maybe contact entry during synchronization. And here I'm stuck. I'd like to underline that this is a critical error. It forces me to manually sync calendar entries from my korganizer to nextcloud, which feeds my smartphone. In the long run, I'd abandon korganizer and work with nextcloud apps only, if this can't be fixed. And, if this is an incident, it highlights the underlying problem: Error messages which are not very helpful to even a computer - literate end user.
For information after trying all the hacks and tricks I learnt using akonadi, I couldn't find how to fix or work around that critical bug. I had to remove the calendar resource, and recreate it from Nextcloud. So far it works again. All that points out the bug to, as always, akonadi and how it (badly) stores data and/or manages errors it introduces. This bug is still critical, a word from devs would be great!