Use the Add-MailboxPermission cmdlet to add permissions to a mailbox.

————————– EXAMPLE 1 ————————–

This example grants Kevin Kelly full access to Ellen Adam’s mailbox.

The Identity parameter requires the full name of the user to be enclosed in quotation marks (“).
Add-MailboxPermission -Identity “Ellen Adams” -User KevinKelly -AccessRights FullAccess -InheritanceType All

————————– EXAMPLE 2 ————————–

This example sets Tony Smith as the owner of the resource mailbox Room 222.

Add-MailboxPermission -Identity “Room 222” -Owner “Tony Smith”

————————– EXAMPLE 3 ————————–

This example grants the user Mark Steele Full Access permission to Jeroen Cool’s mailbox and disables the auto-mapping feature.

Add-MailboxPermission -Identity JeroenC -User ‘Mark Steele’ -AccessRight FullAccess -InheritanceType All –Automapping $false