Environment
Retain 3.2.1 and newer
Exchange 2010
Exchange 2013
Situation
I want to archive a shared mailbox as well as room and equipment resources. What do I need to do so that Retain can access them?
Resolution
Exchange requires that delegation rights be granted to the impersonation account that you are using for your Retain archive jobs, which is listed in the Retain web administration console under Configuration | Module Configuration | Exchange | Impersonation.
If the shared mailbox was John Doe's and your Retain impersonation account were "Retain", you would issue the following command in an Exchange Management Shell (EMC) :
Exchange 2010: Add-MailboxPermission -Identity "John Doe" -User Retain -AccessRights FullAccess -InheritanceType All
Exchange 2013: Add-MailboxPermission -Identity "John Doe" -User Retain -AccessRights FullAccess -InheritanceType All -AutoMapping $false
Note About AutoMapping:
If a user is granted Full Access permissions to another user's mailbox or to a shared mailbox, Autodiscover automatically loads all mailboxes to which the user has full access; thus, we want to disable AutoMapping in 2013. It cannot be disabled in 2010.
To grant the permissions immediately, stop and then restart the Microsoft Exchange Information Store service.
References:
Allow Mailbox Access: Exchange 2010 Help
Add-MailboxPermission: Exchange 2013 Help