The Windows Small Business Server 2003 Transition Pack provides a way for customers to grow out of Windows Small Business Server 2003 into the standard line of server products.
You would purchase the transition pack for the following reasons:
# You need more than 75 users or devices
# You want to separate the Windows Small Business Server components (for example, Windows Server 2003, Exchange Server 2003, or SQL Server) onto separate server machines.
# You want features available only in the enterprise editions of Windows Server System, such as SQL Server 2000 Enterprise Edition or Exchange Server 2003 Enterprise Edition.