Set NTP servers on Windows Server 2008

First, check/set the following registry values :

[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\W32Time\Parameters]
"Type"="NTP"
[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\W32Time\TimeProviders\NtpServer]
"Enabled"=dword:00000001

Then, run the following commands :

w32tm /config /syncfromflags:manual /reliable:yes/manualpeerlist:time.nist.gov,tick.usno.navy.mil,tock.usno.navy.mil,0x8
w32tm /config /update
w32tm /resync