Configure Server NTP Server Windows

1. Stop the time service
   net stop w32time
2. Set the manual peer list external servers
   w32tm /config /syncfromflags:manual /manualpeerlist:"asia.pool.ntp.org"
3. Set the connection as reliable
   w32tm /config /reliable:yes
4. Start the time service back up
   net start w32time
5. Test the configururation
   w32tm /query /configuration
6. Check time source
   w32tm /query /source

Ref: http://techlauve.com/how-to-time-sync-across-windows-network/

Ref: http://community.spiceworks.com/how_to/show/5765-configure-2008-r2-server-ntp-server