Office Communications Server 2007 R2 supports two migration paths, side-by-side and remove/reinstall. The following sections describes the paths and explains why, in most cases, you should use side-by-side migration.

This document is based on the side-by-side migration path.

Before you begin the migration process, you will need to install some updates for the Windows Server operating system. Additionally, with the 2007 R2 release we recommend that you transfer global settings that are stored in the Active Directory Directory Services to a different container.

For more information about these pre-migration tasks, see the following sections: