I am going to be installing 2007 Exchange into my domain that contains a 2003 cluster and a 2003 Front-end. I do have multilpe domains, but Exchange is only in one. When I run EXPBA exchange readiness tool, it says "The Active Directory schema will need to be upgraded (via the /PrepareSchema switch of Exchange Server 2007 setup) before Exchange 2007 servers can be installed into the organization." I believe the /prepareSchema also runs PrepareLegacyExchangePermissions. My question is, do I ONLY need to run the /prepareSchema? What about /prepareAD? Which is it? Thank you

Hi Jason, - You need to run /prepareshema on any server in the AD site where your Schema Master FSMO role is available. - Yes /PrepareSchema runs /PrepareLegacyExchangePermissions if you didnt run it earlier. - You need to run /PrepareAD. - You need to run /PrepareDomain on any of the server in the domain where you are planning to install your Exchange 2007 server or planning to keep Exchange 2007 users and in case you have multiple domains in your AD environment. Further details can be found here How to Prepare Active Directory and Domains http://technet.microsoft.com/en-us/library/bb125224.aspx