The Windows Time Service is configured in much the same way as the forest root PDC Emulator. The main difference is that the server is maintaining its own clock rather than providing an authoritative source for an Active Directory forest.

Choose suitable NTP servers

Select two or more reliable NTP servers. They may be provided by the NTP Pool Project, a commercial appliance, a firewall, a NAS or a local Chrony server. Avoid depending on a single external source where possible.

Configure Windows Time Service

Open an elevated Command Prompt and run:

w32tm /config /manualpeerlist:"0.uk.pool.ntp.org,0x8 1.uk.pool.ntp.org,0x8 2.uk.pool.ntp.org,0x8" /syncfromflags:manual /update

Unlike a domain controller acting as the authoritative source, there is normally no requirement to use /reliable:yes on a standalone server.

Restart the service

net stop w32time
net start w32time
w32tm /resync

The service can also be restarted with PowerShell using Restart-Service W32Time.

Verify the result

Always confirm that Windows has selected the intended source.

w32tm /query /source
w32tm /query /status
w32tm /query /configuration

The configured peer list alone does not prove that synchronisation is taking place.

Testing an NTP server

Where there is doubt about connectivity, test a server directly:

w32tm /stripchart /computer:0.uk.pool.ntp.org /samples:5 /dataonly

This confirms that the server responds to NTP requests but does not make it the selected Windows Time source.

Virtualisation hosts

If the standalone server is a Hyper-V, VMware, Proxmox or XCP-ng host, its own clock becomes particularly important because guest operating systems may inherit the host time during startup. Keeping the host synchronised helps prevent installation, activation and certificate issues in virtual machines.

Common mistakes

  • Using only one external NTP server.
  • Not checking the selected source after configuration.
  • Leaving the server on Local CMOS Clock.
  • Blocking outbound UDP port 123.
  • Changing advanced registry values without understanding their purpose.

Related information