[MICROSOFT 365] – Check users who have Fullacess at a mailbox
Sometimes you should need to check what mailbox a user has full access The command below will help you get all users and check the access rights.
Connect to Microsoft 365 using PowerShell
Connect-MsolServiceSwitch the user@yourdomain.com before executing the code
get-mailbox -ResultSize unlimited | Get-MailboxPermission -User user@yourdomain.com | select identity, user, accessrights