Using Calendar Audit an admin can add additional owners to any existing calendar owned by a user on their domain. G Suite admins are able to add Writers/Readers and Free/Busy for any calendar.
Auditing different Google Calendar Resources
“Free/Busy Reader only” – Provides read access to free/busy information.
“Reader” – Provides read access to the calendar. Private events will appear to users with reader access, but event details will be hidden.
“Writer” – Provides read and write access to the calendar. Private events will appear to users with write access, and event details will be visible.
“Owner” – Provides ownership of the calendar. This role has all of the permissions of the writer role with the additional ability to see and manipulate ACLs.
Adding Additional Owners to a default (primary) calendar
Admins can add additional users onto another user’s primary (default) calendar.
Note: you can add and remove additional owners, but can not remove the original(primary) owner. You can remove and add every other writer and reader.
Users who have been added as additional owners of a calendar will receive an email with a description and a link to open their calendar to view the changes.
The calendar will show under the heading ‘My calendars’, the user will have permission to create, edit or delete events on that calendar. All additional owners will have full control over the original owner’s calendar.
Deleting the original owner from a non-primary calendar
NOTE: If the Calendar is not a primary calendar meaning it’s not the default calendar of a user, admins are able to remove the previous owner after they have added an additional owner.
Adding Writers or Readers to existing calendars owned by users on your domain
When a user is placed on the Writer/Reader field of calendar permission. They will have access to those calendar resources.
Those users will receive an email with a description of what changes the admin has made.
Writer and Reader calendars are displayed under the heading ‘Other calendars’
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