To run reports from the Mailbox Information group, you need full permissions on selected mailboxes, particularly the Receive As and Send As permissions.
NOTE: Even the Full Exchange administrator account does not have Receive As and Send As permissions by default.
Permissions for each mailbox can be individually set using the Mailbox Rights button in Active Directory user properties.
Mailbox permissions can also be set at various levels of the Organization: server, store... For more information on how to set mailbox permissions, refer to the following Microsoft articles:
