In Windows Time Services by default PDC operations master at the root of the forest becomes authoritative for the organization. It is recommended to configure the authoritative time server to gather the time from a hardware source.
These recommendations provide more accuracy and security to your domain.
For more information about this recommendation see the following Microsoft article:
How to configure an authoritative time server in Windows Server 2003.
When you configure an authoritative time server in Windows Server 2003 Windows Time Synchronization does not appear to be working correctly and you receive the following error:
Error Message in the Event Log:
Event Type: Warning
Event Source: W32Time
Event Category: None
Event ID: 12
Time: 3:42:27 PM
Time Provider NtpClient: This machine is configured to use the domain hierarchy to determine its time source, but it is the PDC emulator for the domain at the root of the forest, so there is no machine above it in the domain hierarchy to use as a time source. It is recommended that you either configure a reliable time service in the root domain, or manually configure the PDC to synchronize with an external time source. Otherwise, this machine will function as the authoritative time source in the domain hierarchy. If an external time source is not configured or used for this computer, you may choose to disable the NtpClient.
The W32tm Command generates the following error message:
w32tm /resync /rediscover
The computer did not resync because no time data was available.
This problem occurs if there is a Domain Level Policy applied to the PDC Operations Master role.
Computer Configuration -> Administrative Templates -> System -> Windows Time Service -> Configure Windows NTP Client.
NtpServer = a known NTP Server
Type = NT5DS
Though Registry have been configured to use Type as NTP, it is overridden by NT5DS being applied from the Group Policy.
Remove the Group Policy setting for the PDC Operations Master which has the configuration setting of "Type" = "NT5DS".
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