Hi. I have 2 CentOS machines running both Samba4 using domain "sti.teste". I also have a third machine running Windows 2008 R2 on the same domain, everything working fine. The problem is when i try to add a Windows 2012 Server to this domain.....i got this error on windows AD Domain Services Configuration Wizard (Prerequisites Check): "Verification of prerequisites for Active Directory preparation failed. Unable to perform Exchange schema conflict check for domain sti.teste. Exception: The RPC server is unavailable. Adprep could not retrieve data from the server ad.sti.teste through Windows Managment Instrumentation (WMI). [User Action] Check the log file ADPrep.log in the C:\Windows\debug\adprep\logs\20130215160408-test directory for possible cause of failure." Anyone got success on this setup, Win 2k12 server + S4? Tks!