When migrating mail data from Lotus Notes to Microsoft Exchange you may receive the following warning:
"WARNING: Unable to get unread note table for user '<User>' in database '<DBPath>'; assuming all notes are unread. NSFDbGetUnreadNoteTable: You are not authorized to perform that operation."
This warning is caused when the Administrator is listed in the ACL but not as manager. The archive therefore will migrate, but will lose the read status of all messages.
Verify Administrator is listed in the ACL as a manager and remigrate the data.