Preparing for an Exchange 5.5 to Exchange 2003 Migration

After you have successfully implemented and deployed your Active Directory on Windows Server 2003 and all your Global Catalog Server are Windows Server 2003, you should then make sure that you have updated your Exchange Server 5.5 with Service Pack 3 or higher. If you have deployed Instant Messaging or Exchange Server 2000 Conferencing you should consider deleting them before you update these servers. They will be replaced with Office Live Communication Server 2003; even Mobile Information Server should be deleted, because now it is built in with Exchange Server 2003; so coexistence is not supported.

Exchange 5.5 to Exchange 2003 Migration Summary

If you are migrating an existing Exchange Server 5.5 organization to Exchange Server 2003 is not quite as easy as upgrading, but after the whole procedure you are having a complete newly reconstructed and completely overworked messaging and collaboration system without any old fragments of Exchange Server 5.5. Because implementing Active Directory Services means a restructure of your network with server consolidation. Because Exchange Server 2003 supports about 4 times more users than Exchange Server 5.5, you should think of a migration of your users to Exchange Server 2003 with a complete redesign.

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