We have an AD forest called olddomain.local Windows 2003 active directory with Exchange 2007. We plan to build a new forest called newdomain.local and running Windows 2008 r2 active directory and Exchange 2010. We then want to migrate all mailboxes, user accounts, goups, etc. from one to the other. The reason we are building a new forest as we want to change the internal domain name.
How should I go about doing this?