Launch the Windows PowerShell as an Administrator and use:
Move-ADDirectoryServerOperationMasterRole -Identity [Target DC] -OperationMasterRole 0,1,2,3,4
0 = PDC Emulator
1 = RID Master
2 = Infrastructure Master
3 = Schema Master
4 = Domain Naming Master
Use: “NETDom Query FSMO” to see which server has which role assigned.
Don’t forget to demote your old DC if you are going to decommission it.