To view and update a Calendar's Permissions,
1. Click “Settings” on the admin bar.
2. Select the “Calendars” tab on the left side of the window.
3. Click the Calendar that you want to update the view settings for.
4. Choose the appropriate setting (Nobody, Users, Everyone).
5. Click “Save” to save the change.
6. Click on Close to exit the Calendar Settings page
Note: Nobody keeps the calendar hidden from everyone. Users will allow anyone who can sign in to your site the option to view the calendar. Everyone will allow anyone who visits your site to see the event on the calendar.
Note: Permissions for Group Calendars are managed exclusively through the group the calendar is part of. These calendars' permissions will show as "Disabled" on the Calendar view.