Synchronizing Time

[Shaggy Hiker]

I have a few computers connected over a LAN that all need to be using the same time down to the second. I have some functionality built into my programs currently to send and receive system time via UDP, but it seems like this should not be necessary as more than a check.

Supposedly, Windows can synch a system clock with one of several web based time sources, yet I have tried three or four of these at different times, and I always get a message saying that an error occurred when attempting to synchronize the time.

Has anybody used this feature (open the clock on the system tray and look for the Internet Time tab, if you don't even know what I'm talking about), and if so, does is work?

[si_the_geek]

I get the same issue on my PC, which I have set to update on startup as the cmos battery is flat! From what I have seen, it is quite common for non-networked computers to get this error.

Apparently there aren't similar issues if your computers are networked and you use a time-server.. even if the time-server gets the error (which I'm told is much less likely), the clients still get their time from your time server, so at worst they are synchronised with each other (even if that time is slightly wrong when compared to the rest of the world!).

I don't know how to set up a time server myself, but when I was looking for a fix to my issue I did see a few articles/tutorials about it, so you should be able to find one that suits your situation.

[RhinoBull]

Make sure Windows Time service is started. You can configure it from CP > Admin Tool.

[si_the_geek]

The error occurs even with that service running.. it's been a few months since I looked into the other requirements etc, but when I did everything else was fine too (I also have all appropriate services & registry settings etc, have checked the line, tried different public time servers, made sure there is a connection to the server, ...).

Unfortunately the error is not consistent.. it will often occur for me, usually (but not always) continuing to do so when re-tried.

Despite trying the suggestions in MSKB articles and forum posts etc, nothing has made the error go away, or even reduced the frequency of it.

[RhinoBull]

The error occurs even with that service running...

That has never been the case for me since XP is out - if service is off the error occurs (that of course if server is reachable).

[si_the_geek]

It is unfortunately the case for me, and many others too. I use XP Pro (fully patched), tho apparently the issue also occurs on other versions of Windows too (even fresh installs).

Presumably there is a problem somewhere on my computer or in the connection (eg: at my ISP), but I have not been able to find out what it is - the fact that it sometimes works eliminates many of the likely causes, but doesn't give much of a hint to the real cause.

[tr333]

I was also having problems with synchronizing a windowsXP machine to the time servers on pool.ntp.org. No idea what the problem could be :s

[superbovine]

what does it say in event manager the source and event id?

If the event randomly repeatable have you look into the network being the actually cause? try to ping the time server when it is unreachble etc? try changing time servers? use the navy one vs microsoft etc?

[si_the_geek]

I can't speak for anyone else, but in my case there are no items in the Event Log if there is a failure.

I have checked the network, and there are no issues whatsoever (tho the server(s) at time.windows.com seem to ignore pings, the others respond in 200ms or less). The same problem occurs for all 3 different time servers I have in my list.

[Shaggy Hiker]

Well, Windows Time Services are started, and I have tried this on both XP Pro and XP Home, with no success. Considering what a pain it is, I might as well keep using the system I am currently using via UDP.

[superbovine]

microsoft probably has a nice ACL that block ping, to prevent a DoS.

First, let say I am assuming that your computers are not part of an Active Directory.

From everything in technet it would seem that an event in log would be created which is puzzling. So you are managing to throw an error that doesn't show up in event logs.

You can try manual resync from one of those links below.

http://support.microsoft.com/kb/307897
http://technet2.microsoft.com/window....mspx?mfr=true

hmmm
It uses port 123, if you know enough could sniff your network and watch to see if get any response from the time servers over port 123.

is your router configured to connect to a time server and sync itself? might be causing weird network havoc. check port forwarding as well for that port as well on the router.

However, i am barking up the network troubleshooitng tree because that is the eaiset link to mess with beside windows.

For troubleshooting purposes disable your software firewalls.


Other than that I am out of ideas.

[artstar]

If your computers on the lan are all windows/xp or xp/pro or 2000 and above you can try this.

Check to make sure this file is on your computer. (w32tm.exe)
You may need to register this file. At a command prompt type "w32tm.exe/register." without the quotes.

At a command prompt type:
"Net time /setsntp:time-nw.nist.gov" (Without quotes) hit (enter)
"Net time /querysntp" (Without quotes) hit (enter)
"Net stop w32time" (without quotes)
"Net start w32time" (Without quotes)

Once this has been done. Go to windows services and make sure "Windows time" service is set to (Automatic)

Now for this to work you have to have Internet service.