Exchange Pre-Deployment Analyzer performs an overall topology readiness scan of your environment and provides you with a list of decisions that need to be made before you deploy Exchange Server 2010. You can use ExPDA to perform an overall topology readiness scan of your environment. When you run ExPDA, it provides a detailed report that’ll alert you if there’re any issues within your organization, which could prevent you from deploying Exchange 2010. For e.g., ExPDA will notify you if you haven't deployed minimum required Exchange service pack on all your existing Exchange servers. The checks performed by ExPDA are similar to pre-requisite checks implemented (via Exchange Best Practices Analyzer) in Exchange 2010 Setup program; in fact ExPDA is based off ExBPA engine. However, unlike Exchange 2010 setup, this tool focuses only on overall topology readiness and not the ability to run Exchange 2010 on the local computer.
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