From an administrative command prompt

w32TM /config /syncfromflags:manual /manualpeerlist:<servername or IP>

w32tm /config /update

w32tm /resync

To poll an ntp server for time:

w32tm /stripchart /computer:IPorHostname /dataonly /samples:5

NTP GPO details explained

So what all these settings mean.

Configuring Windows NTP Client: Enabled

• NtpServer: Here you specify which NtpServers to use seperated by a space but also with a special NTP flag. I decided to use the public ntp.org pools:
  0.se.pool.ntp.org,0x1 1.se.pool.ntp.org,0x1 2.se.pool.ntp.org,0x1 3.se.pool.ntp.org,0x1The NtpFlags are explained in detail here but 0x1 means: “Instead of following the NTP specification, wait for the interval specified in the SpecialPollInterval entry before attempting to recontact this time source. Setting this flag decreases network usage, but it also decreases accuracy.” where SpecialPollInterval is specified in the GPO (in our, case 3600 seconds)
• The rest of the settings are explained in the GPO Help.

Enable Windows NTP Client: Enabled

• Is a must, otherwise the computer will not sync with other NTP serves since it’s disabled by default.

Enable Windows NTP Server: Enabled

• Is a must, otherwise the computer will not allow other computers to sync with it since it’s disabled by default.

Where is the configuration store

First, never edit the registry for NTP. If something is not working, clear the configration and start from scratch and configure NTP using GPO or W32tm.exe. Do this by running the following commands:

Stop-Service w32time
w32tm /unregister
w32tm /register
Start-Service w32time

Still, you might want to check where the configuration is. When using GPO, the configuration is stored here:

HKLM\SOFTWARE\Policies\Microsoft\W32Time\Parameters

Note that this is different if you’re using w32tm.exe, then the configration is stored here:

HKLM\SYSTEM\CurrentControlSet\Services\W32Time\Parameters

Useful tools when troubleshooting NTP

W32tm is still your friend and here are my favorites:

w32tm.exe /resync /rediscover /nowait

Resynchronize the clock as soon as possible, disregarding all accumulated error statistics. It will not wait for resynchronization and will force redetection of sources.

w32tm /query /peers

Displays all configured peers you have configured

w32tm /query /source

Displays the currently used time source. Note that after a restart of the service, it might show Local CMOS Clock until everything has refreshed properly.

w32tm /query /status

Displays the current status

w32tm /query /configuration

Displays the configuration

w32tm /debug /enable /file:C:\Temp\w32tmdebug.log /size:10485760 /entries:0-300

Sources