Troubleshooting Windows Time Service Problems

On This Page

Troubleshooting Windows Time Service Errors on a PDC Emulator


If you suspect a time synchronization problem, use the Net Time tool and the W32tm tool to identify time errors. Table 2.15 shows common error messages that these commands display, their root cause, and solution. If the time synchronization problem is occurring on the PDC emulator, see the section following the table (Troubleshooting Windows Time Service Errors on a PDC Emulator).

Table 2.15 Error Messages for Net Time and W32tm Tools

Tool and Error

Root Cause


Net Time: Could not locate a time server.

  • The manually specified time source might not be in the local workgroup or in the domain, or it might not be announcing itself as a time server. Although you received this message, the time service might still be synchronizing time.

  • The time service might not have been stopped before a configuration change was made.

  • UDP port 123 might be closed on the firewall or router between the client and the server or it is being used by another service.

Net Time: Access denied.

A remote procedure call (RPC) failed to authenticate, usually because a user does not have permission to access the remote computer and run Net Time.

If you know the user name and password of an account that does have access rights, establish credentials to access the remote computer to perform this task.

W32tm: Bind failed.

Two instances of the same service are trying to start by using the same port. The Windows Time Service is already using UDP port 123 (the default port for the time service). Therefore, the W32tm tool is not able to use the port.

When you use the W32tm tool, be sure to stop and start Windows Time Service.

Troubleshooting Windows Time Service Errors on a PDC Emulator

By default, no time source is configured on the PDC emulator. As a result, when Windows Time Service is running on the PDC emulator, it sends messages to the system event log indicating that it has no time source. When this error occurs, do one of the following:

  • Configure a manual time source for the PDC emulator of the forest root domain. For more information about configuring a manual time source for the PDC emulator, see "Configuring a Time Source for the Forest" in this guide.


  • Set the PDC emulator to not synchronize time.