ERROR: "[7355-199-25-00000000] Unable to set up user identity from input string" (4209988)

ERROR: [7355-199-25-00000000] Unable to set up user identity from input string = 'user@domain.com', message ID =
Msg: (OF4DDE4678:6013FB8F-ONCA25795F:000E9B67)
Folder: (~CALENDAR)
Subject: (Lunch)
Sender: ("User" <User@Domain.Com>)
Date: (Wed Dec 00 13:55:02 2011)
Original message: notes:///CA25777E001DA8B5//4DDE46786013FB8FCA25795F000E9B67
CPersonMapi::FindEntryID - lookup error

The user listed in the error message does not exist in the Exchange Global Address List, so any rights or permissions could not be granted accurately.

Ensure that all users are properly provisioned in Active Directory and that they have mail attributes or mailboxes prior to migration.