We currently have 2 Exchange 2007 servers in our organization. We are replacing the original server with a new one due to some hardware issues.
The new server is in and functioning well as far as I can tell. All mailboxes are on the new server. I think I've successfully replicated public folders to the new server.
I can stop all the Exchange services, except one, on the old server and still function well.
When we stop the Information Store service on the old server, all the Outlook clients prompt for a password. Once the IS is restarted, all is well again.
I ran get-offlineAddressBook | fl on the new machine and all the references there are to the old server.
So I must be missing something...
I found a couple of articles (below), and some suggestions to just uninstall Exchange from the original server. That seems very risky to me; I'd like to see the new server run for a while with the services stopped on the old one before I uninstall.