When you add a new Windows domain controller running a newer server operating system, you need to prepare the Active Directory Schema by running the Adprep.exe utility. This utility will upgrade the active directory schema and add the new object types required by the new operating system.
You need to run adprep.exe on Windows Server 2008 or earlier versions. Later versions (Server 2012/2016) automatically run adprep during the promotion of the new DC. This utility is located on the installation DVD of the operating system.