TOPIC I have the problem that I want to synchronize my calendars between different devices. To do it, I use my nextcloud instance. Some more information might be in the following mail: https://mail.kde.org/pipermail/kdepim-users/2020-March/013162.html SUMMARY Recurring events cannot be managed between the instances. In fact, there are two problems that are dependant but not equal. Start by having an event that is recurring with multiple instances. STEPS TO REPRODUCE A.1. Remove one of the events in KDEPIM/Akonadi/KOrganizer A.2. Check the removed event in the other devices (either nextcloud itself of Android mobile using DAVDroid) B.1. Remove one of the events in either of the other devices B.2. Check the event in KDEPIM/Akonadi/KOrganizer OBSERVED RESULT In both cases A + B the removal is not synchronized between the devices. EXPECTED RESULT The events get synchronized successfully. SOFTWARE/OS VERSIONS Linux/KDE Plasma: Archlinux KDE Plasma Version: 5.18.4 KDE Frameworks Version: 5.68.0 Qt Version: 5.14.1 ADDITIONAL INFORMATION I tried to investigate a bit. There seem to be different ways to store exceptions in recurring events in CalDAV (see https://www.kanzaki.com/docs/ical/exdate.html). I looked into the raw payload of the event in akonadiconsole. Unfortunately, the value was changed during synchronization very quickly. I could only get a short glimpse that something has happened but I was not able to read anything useful. I just saw that the string defining the exception was not formatted the same as the others. Another try revealed the following: KDEPIM seems to generate exceptions like this: > EXDATE;VALUE=DATE:20200325 The other two solutions use another syntax: > EXDATE;TZID=Europe/Berlin:20200325T220000 > EXDATE;TZID=UTC:20200326T210000