Steps
- Select “iCal calendar settings” in the left navigation.
- Copy the Deskline export URL.
- Create a Deskline source and paste the URL as its import URL.
- Copy the kalenderabgleich.de export URL and add it to Deskline.
- Remove every other calendar connection.
Final step: Remove all old direct calendar connections to other portals from the provider. Only the kalenderabgleich.de calendar should remain connected.