Such things require admin login.

http://tf.nist.gov/service/its.htm

Why not use the built-in function on XP/Vista to synchronize your system clock?

I do have admin rights, I set it up that way, the program syncs to the NIST server perfectly, but Vista doesn't allow the sync software to update the system clock.

Reply to the second reply, the two programs, the built in vista version and the third party version, do not sync at same time.

When using the built in version, I do not have the option readily available to set the update interval, of course I wouldn't even know there was a problem, if I didn't already have the third party app on an older machine, the two clocks can vary as much as 5 minutes, and in EMCOMM (emergency communications) work that is not

good enough, next?

If it is changing to a desired time server (NIST or NTP) and changing update interval that you want, both can be accomplished by the XP/Vista built-in function.

Server:  simply enter the time server address - it should be the one closest to your computer's location.  Make sure the server offers open access - some only have restricted access or by permission.

Microsoft also has an old list of time servers available: http://support.microsoft.com/kb/262680

Update interval:  this is done by editing the registry

[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\W32Time\TimeProviders\NtpClient]

"SpecialPollInterval"=dword:0x00093a80 (604800)

The decimal value in brackets represents the interval in seconds.  Default (604800) is every 7 days, so, for example, to change to update every hour, replace the value with 3600 (remember to click the Decimal radio button before entering the value).  As I recall, there is no need to reboot to use the new setting - you simply update the time manually to enable the new setting.