set authoritative time server windows 2008

It is recommended that you either configure a reliable time service in the root domain, or manually configure the AD PDC to synchronize with an external time source.
Make your PDC a reliable time source for the clients.
The PDC emulator in the root domain, therefore, is authoritative for the time throughout the forest, since all machines will inherit its clock.If you change the value primavera project planner v5.0 to 1 and enter w32tm /config /update, it will change the running configuration of W32TM, the Windows Time engine.If an external time source is not configured or used for this computer, you may choose to disable the NtpClient.Tested on Windows Server 2008 R2 (Build 7600).This is the Windows Time Service (w32time a service which runs on all Windows machines since Windows 2000.Note that the settings for poll interval (.Gov" /syncfromflags:manual /reliable:yes /update 16: ' This command sets AnnounceFlags to 5, ntpserver to the server list and Type to NTP 17: ' Command found here: 18: ' px?Dll (Local) 45: Enabled: 1 (Local) 46: InputProvider: 0 (Local) 47: 1 (Local) 48: 49: vmictimeProvider (Local) 50: DllName: (Local) 51: Enabled: 1 (Local) 52: InputProvider: 1 (Local).Microsoft has published information about doing this.This, of course, does not apply if you are using a special piece of hardware, such as a hardware clock, to keep correct time on your forest root PDC emulator.Have you had to turn on NTP for standalone servers?Figure B, click the image to enlarge.
A default installation of Windows Server 2008 R2 shows this.
Kerberos authentication requires correct time on all clients participating in authentication.