Recipient.DisplayType (Outlook)
Returns a constant belonging to the OlDisplayType enumeration that describes the nature of the Recipient. Possible return values are olAgent - Agent address, olDistList - Exchange distribution list, olForum - Forum address, olOrganization - Organization address, olPrivateDistList - Outlook private distribution list, olRemoteUser - Remote user address, olUser - User address.
You can use the DisplayType property to filter recipients. The DisplayType property corresponds to the MAPI property PidTagDisplayType.
Dim odtDisplayType As OlDisplayType
odtDisplayType = Session.CurrentUser.DisplayType