Winter Forward, Fall Back

Starting this year, daylight saving time is being extended in the United States and Canada. Learn about Microsoft's patch and two scripts that can help make the job of updating Windows machines easier.

Karen Bemowski

February 6, 2007

3 Min Read
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You're probably familiar with the "spring forward, fall back" mnemonic expression to remember the seasons in which you lose and gain an hour of sleep because of daylight saving time. Well, this memory trick no longer works. Beginning this year, daylight saving time is being extended by about four weeks in the United States and Canada, which means the expression would have to be "winter forward, fall back." Somehow, this expression just doesn't do the trick.

As Jim Turner reports in "Daylight Saving Time Is Changing in 2007," starting this year daylight saving time will begin earlier than it has before. It will start on the second Sunday of March (March 11 in 2007) and end on the first Sunday of November (November 4 in 2007). In anticipation of this daylight saving time extension, Microsoft has provided a time zone update for Windows Server 2003 and Windows XP. This update also includes a few other daylight saving time changes in other parts of the world. You can download the time zone update from the Microsoft article "2007 time zone update for Microsoft Windows operating systems." Alternatively, you can edit the registry in Windows 2003 and XP machines, following the instructions provided in the Microsoft article "How to configure daylight saving time for the United States in 2007."

"To the best of my knowledge, this Microsoft update is still considered optional," reports Jim. "I suppose it's possible that Microsoft has embedded some other internal method that will adjust our computer clocks via a previous update. However, I suspect not. Unless Microsoft has (or will) include it somewhere else in its auto updates or patches, come March 11, our computer clocks won't be adjusted if this update isn't applied."

In response to the upcoming changes to daylight saving time, Jim and another Scripting Pro VIP author, Chang Lu, have written scripts that might make your job updating your machines easier:

DST_Test.vbs. The Microsoft update changes the WIN32_TimeZone component. So, Jim has written the DST_Test.vbs script to test whether the WIN32_TimeZone component has been updated on Windows 2003 and XP machines. You can download this script by clicking the "Download the Code Here" link at the top of this Web page. To use DST_Test.vbs, simply place it on the Windows 2003 or XP machine you want to test and double-click it. You'll receive a message box that states whether or not your machine has been updated.

DST_Test.vbs uses the DLS function, which Jim uses in GetDLSDates.vbs and SuperTuesday.hta. GetDLSDates.vbs tells you the dates on which daylight saving time starts and ends in the current year. SuperTuesday.hta is a HTML Application (HTA) that displays the second Tuesday (aka Super Tuesday) of a given month for up to 72 months to get a heads-up on when Microsoft releases its patches. This HTA isn't limited to finding Super Tuesdays. You can use the HTA to get a heads-up on any day of the week of any month. You can download GetDLSDates.vbs from "Don't Let Daylight Saving Time Sneak Up on You" and SuperTuesday.hta from "Plan Ahead for Patch Tuesday.". Note that the Microsoft update just described is needed for GetDLSDates.vbs to work.

SetDSTDates.vbs. Chang has written the SetDSTDates.vbs script to automate the daylight saving time changes in Active Directory (AD) environments. Unlike the Microsoft update, this script applies the daylight saving time changes to Windows 2000 machines as well as Windows 2003 and XP machines. Specifically, you can use the script on the following platforms:

  • Windows Server 2003 x64 Editions

  • Windows Server 2003

  • Windows XP 64-Bit Edition

  • Windows XP

  • Windows 2000 Server

  • Windows 2000 Professional

Chang has written a silent mode version of SetDSTDates.vbs, which is named SetDSTDates_Silent.vbs. In addition, he's written two self-executables so that you can easily execute SetDSTDates.vbs and SetDSTDates_Silent.vbs. Starting on February 14, these scripts and executables will be available in the article "Script Improves Upon Microsoft's Daylight Saving Time Patch" on the Scripting Pro VIP Web site.

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