I manage a mixed windows 2003/2008 Active Directory domain. I've configured the PDC emulator role to obtain it's time from an external NTP reference server using the below command. All other windows servers have been left with their default time configuration :- w32tm /config /manualpeerlist:SERVER NAME /syncformflags:manual /reliable:yes /update Unfortunately, although all my windows machines are synchronised with the PDC emulator, the PDC emulator is approximately 80 seconds behind the NTP reference server. I've attempted to use the below command to fix the problem on but receive an 'ACCESS DENIED' message (despite being looged in as a Domain Admin). w32tm /resync /computer:SERVER NAME Any ideas ?

On the PDC (assuming 2003 PDC) use the following command to set external time source net time /setsntp:external.dns.com Stop and restart the Windows Time Service. On 2008 you must use the w32tm command to set the external NTP source for the domain. Then stop and start the time service. Review the event logs to verify the time service is communicating with the external time source, if a failure occurs it will be logged. More Information: http://networkadminkb.com/kb/Knowledge%20Base/Windows2003/How%20to%20reset%20W32Time%20to%20sync%20time%20with%20the%20domain.aspx http://networkadminkb.com/kb/Knowledge%20Base/Windows2003/W32Time%20does%20not%20synchronize%20time%20with%20any%20time%20source.aspx http://networkadminkb.com/kb/Knowledge%20Base/ActiveDirectory/How%20Active%20Directory%20Time%20Synchronization%20Works.aspx

in addition to that try to run the command from the elevated permisson and check, by the way Microsoft says the time service has a tolerance of 2 minutes, and if anything less, it ignores the difference.

Hi, The PDC Emulator is running windows 2008 R2, so I've used the w32tm command specified earlier to sync with the reference server. I've checked the event logs (in particular SYSTEM) but can't see any errors. The problem is that the time on the PDC emulator doesn't appear to be getting any closer to the reference server - it's always at least 80 seconds out. Thanks.

Hello, there is nothing to worry about. Microsoft time services are not built for high accuracy and up to 120 seconds isn't problem at all. In a domain you can have the max. difference from 600 seconds, default Kerberos required time. More details in: http://msmvps.com/blogs/mweber/archive/2010/06/27/time-configuration-in-a-windows-domain.aspx Especially see: http://blogs.technet.com/b/askds/archive/2007/10/23/high-accuracy-w32time-requirements.aspxBest regards Meinolf Weber Disclaimer: This posting is provided "AS IS" with no warranties or guarantees , and confers no rights.

Hi, Thanks for the replies. I understand that 80 seconds time difference with the NTP reference server isn't really a problem for Windows. However, is there a way of occasionally forcing the time to resynchronise, so that the time on the PDC emulator and NTP reference server match (albeit the time may drift again slightly).

Try this command w32tm /resync [/computer:<computer>] [/nowait] [/rediscover] [/soft] Tell a computer that it should resynchronize its clock as soon as possible, throwing out all accumulated error statistics. computer:<computer> - computer that should resync. If not specified, the local computer will resync. nowait - do not wait for the resync to occur; return immediately. Otherwise, wait for the resync to complete before returning. rediscover - redetect the network configuration and rediscover network sources, then resynchronize. soft - resync utilizing existing error statistics. Not useful, provided for compatibility.