DO NOT clear the storage of the Calendar app or Contacts (unless you want to lose all your app settings). If you clear the storage of the Calendar or Contacts app, the contacts and calendar events will not be deleted, but all your app settings will be!
The /e/OS Calendar app is basically a window on to the data stored by the Calendar Storage system app (as are any other calendar apps you might install) . To delete all your calendar events you need to clear the storage of that app, not the Calendar app.
Similarly, the Contacts app is basically a window on to the data stored by the Contacts Storage system app (as are any other contacts apps…). To delete all your contacts you need to clear the storage of that app, not the Contacts app.
When you follow the steps below, only data which is stored locally (i.e. events in any offline Calendars you created, or contacts in the Device account) are deleted permanently. Data stored in online accounts (your eCloud / Murena account, other CalDAV and CardDAV accounts) will be restored to your device the next time you sync your device.
These are the steps to follow
- Settings | Apps | Show all
nnnapps - From the ‘3 dots’ menu choose ‘Show system’
- Scroll down and click on ‘Calendar Storage’ or 'Contacts Storage`
- Click Storage and cache, then Clear storage
When you open the Contacts or Calendar app now, all your contacts or calendar have gone. Any that are held in your online accounts should reappear the next time you sync the accounts.