I'm currently evaluating switching to groups for a K12-school. But as I can't have students adding and removing bookings from the group calendar, I'm looking for a way to set read-only permissions. I've seen some reference to using the set-unifiedgroup cmdlet and changingCalendarMemberReadOnly, but I can't get it to work.
Have you already tried -CalendarMemberReadOnly $true ?
Yes I have, it make no difference. According to the Set-UnifiedGroup technet-page it should be without $true, "To set read-only Calendar permissions, use the CalendarMemberReadOnly switch without a value."