1. 修改注册表项
   HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\W32Time\TimeProviders\NtpServer     
(默认0)
   HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\W32Time\Config\
(默认 10)
ValueMeaning

0

Timeserv_Announce_No, Reliable_Timeserv_Announce_No. The domain controller does not advertise time service.

1

Timeserv_Announce_Yes. The domain controller always advertises time service.

2

Timeserv_Announce_Auto. The domain controller automatically determines whether it should advertise time service.

4

Reliable_Timeserv_Announce_Yes. The domain contoller will always advertise reliable time service.

8

Reliable_Timeserv_Announce_Auto. The domain controller automatically determines whether it should advertise reliable time service.

2. 禁用防火墙或设置例外,UDP 123端口。
3. 运行 services.msc,将Windows Time服务设置成自动(延迟启动)
     Win7下如果设置成自动,下次重启后此服务会被停止,原因不详。
     经实验,延迟启动也并不需要用户登录即可启动。
4. 重启动校时服务:net stop w32time && net start w32time 
 
网络设备(如cisco、h3c交换机……)不能正常同步NTP服务器时间:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\W32Time\Config\LocalClockDispersion
值修改为0 (默认为0x0000000a)
05-28 17:20