Ever had EV fail to create a MAPI session and complain the mailbox doesn't exist returning 0x81002746? Well after all these years I just spotted the following posted by MAPI guru Stephen Griffin...
http://blogs.msdn.com/b/stephen_griffin/archive/2011/10/13/the-elusive-0x81002746-error.aspx
Hopefully this gives you the detail you've been craving...
Enjoy :)
-Karl
