I’m in the middle of an Exch2003 migration to Exch2010. I have started moving mailboxes over to the new Exch2010 server but most are still on the old server. I have also created a new user mailbox on the new server but for some reason, in Outlook, I don’t see her. Even if I manually send/receive the address book. I checked to see if she shows up in OWA and sure enough she is there. Just seems like Outlook is not updating the GAL.
I also tested with a user that is still on the old Exch2003 server and he has the new user.