I am in the process of upgrading my Windows SBS 2008 server running Exchange, Active Directory and as a File server to Windows Server 2012 essentials. Now I know that Windows Server 2012 essentials does not have exchange, thus I was looking to migrate the Active directory and the file server to Windows Server 2012 essentials, Then I would have a separate Virtual machine running Windows server 2012 standard with Exchange 2013. Now my question is, what should I do first? Migrate the AD and File server to Windows 2012 essentials and then after the migration is finished, I create a local move of the mailboxes from SBS 2008 to Windows Server 2012 standard running exchange 2013? or should this be the other way round?