I use a third-party Network Time Protocol (NTP) client on most of my company's Windows 2000 network servers to synchronize the network with NTP servers on the Internet. But occasionally the clocks on a few of the network clients get thrown out of sync with the servers, preventing the client machines from logging on to the network. How can I resolve this problem, aside from installing the NTP client on every machine?

Clients and servers in an Active Directory (AD) domain get the time from an authoritative time server, usually the PDC. In your situation, the Windows Time service (W32Time) isn't functioning properly on most of your servers—including the PDC, most likely—because of a port conflict with the third-party NTP client. Therefore, the time on your client machines can't stay in sync with the time on your servers.

To determine which server is acting as the authoritative time server on your network, open a command prompt on a server and type

w32tm ­v

This command will provide information about W32Time; one of the lines will list the authoritative time server. For a complete list of command-line options for W32Time, type

w32tm /?

Although you can manage a third-party NTP client and W32Time on the same server, doing so can become tedious. I suggest you remove the third-party NTP client from your servers and instead use W32Time to sync your machines with the external NTP servers. For more information about implementing W32Time on Win2K systems, see Getting Started with Win2K, "Perfect Timing," November 2002, http://www.winnetmag.com, InstantDoc ID 26697.