Issue: Users are not able to share full details or limited details calendar. Then prompted an error “Policy does not allow granting permissions at this level to one or more of the recipient(s). Please select another permission level and send the sharing invite.” “Availability Only” is the only working.
Cause: This error is because of the sharing rule that is configured to share only the availability. It is not configured to share Full Details.
Resolution: Open Exchange Admin Center (EAC) and go to Organization à Sharing à“Default Sharing Policy”.
Under Individual Sharing, open Default Sharing Policy.
You can see anonymous configured for all but sharing will all domain is configured for information only.
This 1st rule tells that you can only share “Availability Only” permission with the other organizations.
You can either change sharing rule in the sharing policy to “All calendar appointment information, including time, subject, location and title” for all domains
or
Create a new sharing rule for your smtp domain which is shared in the office 365 and assign “All calendar appointment information, including time, subject, location and title“.
Then click on save.
Now If you will share the calendar with full details or limited details then it will send the email and allow office 365 user to see your calendar.