I think what you want is the EntryID of the item, which is accessible from
the Outlook object model or from other API's like CDO 1.21 or Extended MAPI.

--
Ken Slovak
[MVP - Outlook]
http://www.slovaktech.com
Author: Absolute Beginner's Guide to Microsoft Office Outlook 2003
Reminder Manager, Extended Reminders, Attachment Options
http://www.slovaktech.com/products.htm


"Bickers" wrote in message
...
Hi,

I need to track messages in a database, but be able to handle the same
message being sent to multiple recipients (within an Exchange
environment).

I know that all messages sent to multiple recipients will have the same
MessageID value, but I can find no information as to how to retrieve it.

What I'm planning is that when a message is opened, an AddIn will check
whether the message has already been handled and if not, store info in a
database (simplistic view). When another user reads the same message, I
need
to be able to detect that it's already been handled.

Thanks for any help,

Phil.