Outlook folder Automapping

If you assign permissions to a an exchange user or folder using Powershell to a folder you can define if that Folder should be automatically displayed (or auto-mapped) when Outlook next starts.  . If a user is granted Full Access permissions to another user's mailbox or to a shared mailbox, Outlook, through Autodiscover, automatically loads all mailboxes to which the user has full access. This parameter accepts $true or $false values.

eg:

Add-MailboxPermission -Identity JeroenC -User 'Mark Steele' -AccessRights FullAccess -InheritanceType All -AutoMapping $false

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