CalDAV / CardDAV allow delete via Synchronization The CalDAV / CardDAV features are available only for Enhanced mailboxes. Due to a bug in Android 12 some phones started to delete contacts via Microsoft ActiveSync. Therefore, GroupOffice has implemented a new CalDAV / CardDAV setting that disallows deletes via sync by default now. More info on the bug can be found here: https://eu.community.samsung.com/t5/galaxy-z-fold-z-flip/outlook-contacts-gone-after-android-12-update/td-p/4567744/page/2 . Because this option is disabled by default, you might now receive this error in your CalDAV / CardDAV client: Deleting is disabled by user sync settings To enable delete via synchronization: Go to the  Webmail Log in using your full  e-mail address  and your  current e-mail password Click on the  User  icon from the top right to activate the menu. Then click on  My account   In the  Synchronization  tab, find the  Allow delete via synchronization  section. Enable the feature using the checkmark Click on the  Save  button.