MailItem.PermissionService Property (Outlook)
Sets or returns an OlPermissionService constant that determines the permission service that will be used when sending a message protected by Information Rights Management (IRM). Read/write.
This property is useful only if you have more than one permission identity for a particular SMTP address.
While you can view content that is protected by IRM on any computer running the 2007 Microsoft Office system or a later version, you must have Microsoft Office Professional Edition 2003, Microsoft Office Outlook 2007, or a later version of Outlook to create or send an e-mail that is protected by IRM.
This Microsoft Visual Basic for Applications (VBA) example demonstrates how to specify the permission service before sending an item. Replace 'Dan Wilson' with a valid recipient name before running this example.