Event ID 23 — Symmetric Time Source Peer Synchronization

Applies To: Windows Server 2008

The Windows Time service (W32time) is synchronizing with a validated, symmetric time source peer. When a time client and time server are functioning in a symmetric time synchronization mode, they maintain a small amount of status information. This is in contrast to unsymmetric mode, in which no status information is maintained. You can determine the mode of communication by reviewing the communication packets that are exchanged. If the client and server are exchanging network communication packets using the destination Network Time Protocol (NTP) service port number 123, the time synchronization mode is symmetric. If the destination and source ports are different in the network communication packets, the communication mode is unsymmetric.

Event Details

Product: Windows Operating System
ID: 23
Source: Microsoft-Windows-Time-Service
Version: 6.0
Message: The time provider NtpServer encountered an error while digitally signing the NTP response for symmetric peer %1. NtpServer cannot provide secure (signed) time to the peer and will not send a packet. The error was: %2


Investigate possible causes for invalid responses

The error in Event Viewer should provide additional information. This may be the result of a network transmission or configuration error or an attempted computer security attack. Confirm that replication is working properly in the domain.

For instructions for confirming that domain replication, see article 229869 in the Microsoft Knowledge Base (http://go.microsoft.com/fwlink/?LinkId=84803).


To perform this procedure, you must have membership in Administrators, or you must have been delegated the appropriate authority.

To verify that the Windows Time service is synchronizing correctly:

  1. Open a command prompt as an administrator. To open a command prompt as an administrator, click Start. In Start Search, type Command Prompt. At the top of the Start menu, right-click Command Prompt, and then click Run as administrator. If the User Account Control dialog box appears, confirm that the action it displays is what you want, and then click Continue.

  2. At the command prompt, type W32TM /resync, and then press ENTER.

  3. At the command prompt, type W32TM /query /status, and then press ENTER.

    This command displays the status of the Windows Time service synchronization. The Last Successful Sync Time line of the output displays the date and time that you ran the W32TM /resync command in the previous step.

For more information about the Windows Time service, see Windows Time Service Technical Reference (http://go.microsoft.com/fwlink/?LinkID=25393).

Symmetric Time Source Peer Synchronization

Active Directory