what make system time changes?

[ykffc]

OS: Windows 2000 server

When we had Daylight saving time effective weeks ago, the system time of
this machine failed to adjust automatically (although I have the checkbox on
to adjust automatically). I can understand this as Microsoft no longer
supports this old version of OS and they no longer produce updates/patches
for this.

For software compatibility and other reasons we haven't upgraded this
machine. However, I don't think it should be the end of the world. It is a
matter of seconds to adjust the time by hand.

Two days ago I started to adjust the system time from say 13:15 to 14:15
(2:15 pm). But after a while, say after 30 minutes, it was discovered that
the system time changed itself back to 13:45. It looks like something in the
background is changing the time automatedly. I tried a few times in two days
but all failed the same way. Why is that?

I have tried to set & unset the "automatic adjust DST" checkbox, reboot the
system more than once. Nothing helps. BTW, the machine is part of a domain
but I doubt if that matters. I have't heard of a policy that could affect the
time !?

I heard about software that sounds like "atomic clock synchronization" which
might make a machine to automatedly set its time in line with something. But
this is obviously not what we shall do with this machine. Can someone tell
me what are the other functions that might change the system time of a
machine in the background?

thanks.

 

[John John (MVP)]

Of course it matters if the machine is part of a domain. Is the time
properly set on the domain controller?

Basic Operation of the Windows Time Service
http://support.microsoft.com/kb/224799/

John

 

[ykffc]

Thank you John.

Before I found the Primary DC was not set correctly but the secondary was
(all DC runs Win2003 server). Time were both correctly set already but still
exactly the same problem. I need to read your recommended KB.

 

[John John (MVP)]

You're welcome. Another thing that might be affecting this is if
incorrect changes were made when applying DST fixes for the new(er)
dates. Someone might have done this manually with tzedit and they may
have gotten the dates wrong or they may have changed the GMT bias... or
the machine might simply be set in the wrong time zone.

John

 

[TestTurtle]

Try this utility...it also can auto set:
http://tf.nist.gov/service/its.htm
and this:
http://www.grystmill.com/articles/tz_update.htm

Please read the pages/docs first and you'll be fine.