This Active Directory domain controller currently performs the schema master role. If you remove Active Directory Domain ...

This Active Directory domain controller currently performs the schema master role. If you remove Active Directory Domain Services (AD DS) from this computer, you will no longer be able to modify the schema for this forest. Before you continue, transfer the schema master role to a domain controller in the root domain in the forest. If it is not possible to transfer the role, first remove AD DS from this computer, and then use Ntdsutil.exe to seize the role. Use Ntdsutil on the domain controller that you plan to seize the role to; if possible, use a recent replication partner in the same site as this domain controller.  For more information about transferring and seizing operations master roles, see article 255504 in the Microsoft Knowledge Base (http://go.microsoft.com/fwlink/?LinkId=80395).