When configured correctly, you can use the Windows Time (W32Time) service as an SNTP/NTP server for both windows and non-windows SNTP/NTP clients. Start “regedit”, and locate this key: HKEY_LOCAL_MACHINESYSTEMCurrentControlSetServicesW32TimeConfig … and set the “AnnounceFlags” parameter value to 5 To Enable the NTPServer, locate this key: HKEY_LOCAL_MACHINESYSTEMCurrentControlSetServicesW32TimeTimeProvidersNtpServer …and set the “Enabled” parameter value to “1″ Exit the Registry Editor Run the following commands to restart the Windows Time service: net stop w32time net start w32time

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How to Set Up a Windows 2008 R2 SNTP / NTP Server