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Adjust Internet Time Synchronization

By: Arie Slob

Windows XP has the capability to automatically synchronize the clock on your system with an Internet time server. By default, only two servers are provided: time.windows.com and time.nist.gov. You can add additional time servers:

  1. Start the Registry Editor
  2. Go to HKEY_LOCAL_MACHINE \ SOFTWARE \ Microsoft \ Windows \ CurrentVersion \ DateTime \ Servers \
  3. Right-click an empty space in the right pane and select New > String Value
  4. Name the new value with a number one higher than the last (so the first you add will have the value 3, since 1 and 2 are given)
  5. Double-click this new value, and enter the hostname as it's Value data
  6. Close the registry editor

Adjust Internet Time

Here are a few servers you can use:

  • clock.isc.org
  • europe.pool.ntp.org
  • north-america.pool.ntp.org
  • 128.105.37.11

The best you can do is to have a look at this Web site, and select a server close to you.

Note that if you use a firewall, you might have to add the server you use to have access to your computer/network. The Time Service uses the post 123 on the local system.

Adjust Interval

The time interval of the update is set at 7 days. This can be changed in the registry:

  1. Start the Registry Editor
  2. Go to HKEY_LOCAL_MACHINE \ SYSTEM \ CurrentControlSet \ Services \ W32Time \ TimeProviders \ NtpClient \
  3. Double-click the SpecialPollInterval value, and change the Base of the Value data to Decimal
  4. Now change the Value data to the time interval you desire, noting that the time is given in seconds (so for 1 day the value would be 86400, while the default (7 days) is 604800
  5. Close the registry editor

Change the Base of the 'Value data' to 'Decimal'

This is one of the functions performed by:


Tweaking Toolbox XP