This might help to solve your problem: Microsoft Exchange Server MAPI Client and Collaboration Data Objects 1.2.1
I haven't posted much here so i can't link yet but search google for the following:
mapi download exchange 2007
Starting with Exchange 2007 Beta 2, neither the Messaging API (MAPI) client libraries nor CDO 1.2.1 will be provided as a part of the install of the product. As a result, there is functionality missing that many applications depend on. Microsoft Exchange MAPI and CDO 1.2.1 provide access to these APIs, which, in turn, provide access to the contents of MAPI stores.