Microsoft Windows December 2012 Updates for Daylight Saving Time and Time Zones

The latest cumulative update for supported Microsoft’s Windows operating systems addressing daylight saving time and time zone changes is now available on the Microsoft Download Center. This update supersedes and replaces older updates released previously as noted in the full Knowledge Base article, namely KB 2756822 released in October. All additional time zone changes released as hotfixes after the update 2756822 are incorporated into this update.

It contains the following changes:

  • Bahia Standard Time: Starting in 2012, Bahia Standard Time will no longer have DST.
  • Azores Standard Time: Changes reflect the end of DST on October 28, 2012 for Azores Standard Time. These changes were released as KB2769756.  This update includes the changes for DST for Azores Standard Time in Windows 8 and Windows Server 2012. Additionally, this update includes the changes found in KB2769756. The new rules for DST for 2013 and onwards were released as part the October 2012 cumulative time zone update in KB2756822.
  • Fiji Standard Time: The government of Fiji has announced new DST rules for 2012 through 2013. DST starts at 2:00 A.M. on Sunday October 21, 2012 and ends at 3:00 A.M. on Sunday January 20, 2013. This update applies to Windows 8, Windows Server 2012, Windows 7, Windows Server 2008 R2 and down. Additionally, the changes that are included in the October 2012 cumulative time zone update that is described in KB2756822 are found in this update.
  • Jordan Standard Time: Changes the UTC offset for Jordan Standard Time from (UTC+2) to (UTC+3). Therefore, the display name of the time zone is changed to (UTC+03:00) Amman. From 2013 onwards, Jordan Standard Time will no longer have DST.

So what should you do to make sure that your computers are ready for the change?

Most applications and services reference the underlying Windows operating system for their date and time related rules, with some exceptions. We outline the various software updates to select Microsoft products (including various releases of the Microsoft Windows operating systems, Microsoft Office and other applications) on the Microsoft Daylight Saving Time Help and Support Center. There, we have information and links to updates for various products in mainstream and extended support affected by this change, as well as other various changes to DST offsets and time zones around the world.

If you use Microsoft Update on your PC at home, chances are you’re already covered. The latest update from October may already be installed on your PC if you have turned on Automatic Update in Windows. This ensures you’ll get the latest security and other important updates from Microsoft automatically. If you’re not sure if the update has been applied, visit the Microsoft Update site for more information.

If someone manages your network at work, it’s likely the needed updates are schedule to be deployed to your computers and devices, if they haven’t been installed already.

For IT professionals managing PCs, servers and Microsoft software installations, please visit for more details. Also, visit the support websites of any other software companies to see if you need to apply any updates. It’s not just Microsoft software that may require updates. Additionally, for the change in Russia, we provide specific details and guidance in country at

While Microsoft’s Services infrastructure will be updated to reflect DST changes, it’s important that your computers — both clients and servers that interact with these services — also have the latest Windows cumulative updates for DST and time zone changes applied in order to ensure data integrity.

As always, thanks to the good folks in Windows and those across the company working to help manage time… especialy the number of daylight saving time and time zone changes that come in from various corners of the world. You can find this and much more documented over at and over on the Windows blog at


Tags: Windows, Microsoft, Daylight Saving Time, Daylight Savings Time, RSS, DST.

Also available via


It’s Time To Fall Back An Hour in the US and Canada: Daylight Saving Time Ends This Sunday

Drawing of a man holding back the hands of a clock with the caption "You can't stop time"

How quickly time flies, seems like just yesterday we were Springing Forward (way back on Sunday, March 11). Yes, it’s that time again if you’ll pardon the pun, to fall back in much of the Northern Hemisphere.

Daylight Saving Time ends on Sunday, November 4, 2012 at 2:00AM local time in much of the U.S and Canada, except in parts of the countries (including Hawaii and Arizona). For some folks in my old home north of the boarder, Daylight Saving Time means most Canadians will get an extra hour of sleep. Our friends in much of Europe have already bid goodbye, adieu, auf wiedersehen, gesundheit, farewell to European Summer Time, as they fall back on the last Sunday in October each year. (Not to worry, they’ll get back up and Spring forward again on the last Sunday in March.) For our friends in Russia, I’m not sure what the next few months will bring given the back and forth we’ve seen in the country in regard to policies, but safe to assume for now there is a state of détente in the Federation.

You can read more than you’ll ever want to know about DST here and on our official Microsoft Daylight Saving Time Help and Support Center at DST in much of the US and Canada ends in accordance with the US Department of Energy’s Energy Policy Act of 2005 that was passed into law. DST ends later than it did prior to 2007, on the first Sunday of November; more details on the new DST start and end times can be found here). This results in a new DST period that is approximately three to four weeks longer than in past years.

Also important to note, but often ignored: the switch to daylight saving time also means the time zone suffix changes in North America, now using Daylight Time: for example, Pacific Standard Time is now Pacific Daylight Time (aka PDT). The other time zones move to Mountain Daylight Time (MDT), Central Daylight Time (CDT), and Eastern Daylight Time (EDT).

National Geographic has a very interesting article on “Daylight Saving Time – Why and When Does It End” (including a very cool photo of the display model of the inner workings of a clock at the China Science and Technology Museum in Beijing). As you may know (especially if you’re geek familiar with my woefully ignored blog – been busy!) the quite historical Benjamin Franklin pioneered the daylight saving time, as noted in David Prerau’s book Seize the Daylight: The Curious and Contentious Story of Daylight Saving Time. And of course, you’re likely much too young to recall the move by the U.S. Government in the 1970s to extend DST (back when the price of gas jumped nearly 50% to about 55 cents a gallon in the States)…

“During the 1973-74 Arab oil embargo, the U.S. once again extended daylight saving time through the winter, resulting in a one percent decrease in the country’s electrical load, according to federal studies cited by Prerau.”

“OK, that’s all nice and such, but what do I need to do besides set my kitchen clock back an hour?”

As I noted in this article, Microsoft strongly recommends that DST and time zone updates be installed on all affected systems, devices and applications to ensure consistency with current DST rules and time zone settings worldwide. Customers should review the product updates available and posted on this site and at for the latest and updated information of Microsoft products affected by daylight saving time.

Here’s more coverage on DST this year from Bing News.

On a personal note, remember to keep things in perspective. Time is a precious thing. Never waste it

Have a good weekend, and don’t keep too much of that Halloween candy around. As noted here, you can thank candy makers for some of the politics behind DST.

Tags: Microsoft, Daylight Saving Time, Daylight Savings Time, DST.

References to DST on Bing: 1,700,000.

Share this post: Bookmark and Share

Also available via