More DST 2007

This is turning into a REALLY REALLY BIG issue. 

To be clear the new DST change periods are: March 11, 2007 to April 1, 2007 and from October 28, 2007 to November 4, 2007.

New DST Start

March 11, 2007
(three weeks earlier)

Previous DST Start

April 1, 2007

Previous DST End

October 28, 2007

New DST End

November 4, 2007
(one week later)

 So Microsoft Articles to date are:

Blackberry Articles: US Daylight Saving Time Changes and Blackberry

IBM Articles: Lotus software- Daylight Saving Time (DST) changes for 2007 will affect Lotus software products

Also remember that any other Application that uses CDO will need to be updated.  Check with your Application vendor first.

Outlook is looking like it’s going to be a pain in the butt.  The problem is that when you apply the Windows Operating System Update for DST 2007 you will have Outlook calendar appointments off by 1 hour during the DST Change periods.

The solution requires three things to be in place for Outlook calendar items to be updated properly.

  1. The Operating System update to change the time zone information.  928388 or 914387 (available now).
  2. The Exchange Server 2003 Update for CDO.  926666 (available now).
  3. The Outlook Time Zone Data update Tool and the Exchange Time Zone Update Tool. (not released yet).

If all of these patches and tools are not used together, then there will be calendar inconsistencies.  If you install update 928388 or 914387 for the operating system without doing anything else, users are notice that the meetings during the DST change periods are ahead by 1 hour.  This is expected behavior without installing the Exchange server hotfix 926666 patch and using the Outlook or Exchange tool to rebase the appointments that are in the DST change period. 

The Outlook tool is due to be released in January 2007 through the Microsoft Download Center that can update calendar items in Outlook to accommodate the changes in DST during the Extended DST period. This program is called the Time Zone Data Update Tool for Microsoft® Office Outlook® (Time Zone Data Update Tool).
Microsoft Office Outlook 2007, the newest version of Outlook, has the ability to automatically detect the DST change and prompt the process that updates a person’s calendar to conform to the new daylight saving time rules. However, the Time Zone Data Update Tool contains enhancements that improve upon what is available in Outlook 2007and should be run instead of the out-of-the-box Outlook 2007 experience.

The Time Zone Data Update Tool is necessary to update calendar items that occur during the Extended DST periods for the following earlier versions of Microsoft Outlook:

  • Microsoft Office Outlook 2003
  • Microsoft Outlook 2002
  • Microsoft Outlook 2000

The following table describes the situations when you should download and run the Time Zone Data Update Tool:


Outlook 2007 Outlook 2003, Outlook 2002, Outlook 2000
Not required to use the Time Zone Data Update Tool. But it is highly recommended because it includes numerous improvements. Run the Time Zone Data Update Tool.
In environments running Microsoft Exchange, a special version of the Time Zone Data Update Tool may be used to update multiple Exchange mailboxes on the server. In environments running Microsoft Exchange, a special version of the Time Zone Data Update Tool may be used to update multiple Exchange mailboxes on the server.


Check out the scenarios at the bottom of 931667 and MAKE SURE YOU READ THIS:

In the mean I will keep an eye on the Exchange Download Centre (

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