I have just started the process of migrating from exchange 2003 to 2010. I have checked that I have met all prerequisites using the Pre-Deployment Analyzer tool and started the installation of the CAS role. Upon completion of this, the first message/error I recieve is: “Setup is going to prepare the organization for Exchange 2010 by using ‘Setup /PrepareAD’. No Exchange 2007 server roles have been detected in this topology. After this operation, you will not be able to install any Exchange 2007 server roles.”
1. What will this do to my existing mail server if anything?
2. Will this cause any problems or disruption in service?
3. Will they coexist separatly or be working together after I begin the installation?
4. Can I continue installing all roles for Exchange 2010 without loss of service to my exchange 2003 till I move the mailboxes and change my internal firewall rules?