Does anyone know of any issues related to me introducing an Exchange 2010 box into my environment that would negatively affect an existing installation of Unity Unified Messaging? The goal overall is to eventually move Unity to the exchange 2010 box, but I need to get some things up and running and tested before completing a full migration, so my question really relates to the AD schema changes that Exchange 2010 will complete when introduced to my domain. I do not plan to host unified mailboxes on the new box until after I have implemented a full Unity transition plan.
You can add Exchange 2010 to your environment and it will not effect Unity at all. The only time adding any type of Exchange server to AD will effect Unity is when you move subscribers on to it. So you can add it and do whatever testing you want, but before you move 1 Unity subscriber on to that Exchange server, you will need to follow the steps in the following guide: