I am planning a Unity upgrade from 4.0(5) to 7.2. We are running Windows 2000 Server, SQL 2000 SP4, and Exchange 2000. I would like to upgrade all of these apps except SQL. I have the Unity, message store 2003, and server 2003 Media. Can someone tell me what the correct path would be. Upgrade OS, then, exchange, then Unity? What do I need to be aware of? Any help would be appreciated.