Exchange Server 2010 cannot be installed
Applies To: Windows Small Business Server 2011 Standard
Problem Exchange Server 2010 cannot be installed.
Features affected The messaging component of Windows SBS 2011 Standard was not installed. Email messaging is not present and is not functioning.
Resolution See article 2527626 in the Microsoft Knowledge Base.
You can also contact Microsoft Product Support to receive support in isolating the source of the failure so that you can correct it before restarting the migration process.