2007 Daylight Saving Time Changes

Update: See our 2007 Daylight Saving Time FAQ for additional information.

The Energy Policy Act of 2005 was passed to help alleviate energy concerns across the nation. One part of the act that will affect computers is the extension of Daylight Saving Time by four weeks. Instead of changing to Daylight Saving Time on the first Sunday of April, it will now begin on the second Sunday of March. Additionally, it will now end on the first Sunday of November rather than the last Sunday of October. These time changes will still all take effect at 2 a.m. on their respective days.

Changes In Daylight Saving Time
Previous DST Start	New DST Start	Previous DST End	New DST End
First Sunday in April	Second Sunday in March	Last Sunday in October	First Sunday in November
April 1, 2007	Now March 11, 2007	October 28, 2007	Now November 4, 2007

Some computer operating systems and applications are already updated to reflect this change. Others may require patches to be downloaded to operate properly with the change. Below is some information to help with the impact.

Please contact the ITS Help Desk at 384-4357 (4-HELP) or its-helpdesk@uiowa.edu if you have additional questions.

Known Applications

Application/OS	Status
Windows Vista	No Update Needed
Windows XP (SP2), Window Server 2003	Update Required
Windows 2000	Hotfix available to the UI community
Mac OS 10.3.9 or later	No Update Needed
Mac OS 10.3.8 or earlier	Upgrade to 10.3.9 (or later) or Manual Update
Outlook 2007	No Update Needed
Outlook 2003, XP, 2000	Run "Time Zone Data Update Tool"
Entourage 2004	Install Office 2004 Update 11.3.3
Windows Mobile Devices	Update Required
Exchange Calendar Guidelines	Guidelines on dealing with Exchange calendars

Microsoft Windows Vista

Windows Vista does not require any update to be installed for the DST changes. Applications running on Windows Vista may need to be updated (e.g. Outlook, etc.).

For more information see Microsoft's web site at http://www.microsoft.com/windows/timezone/dst2007.mspx

Microsoft Windows XP (SP2) and Windows 2003 Server

Microsoft Windows XP (SP2) does require a patch in order to recognize the changes to Daylight Saving Time. Currently the patch is an "optional" download though Windows Update - Microsoft has indicated it will become a "critical" download on February 13th.

The Windows XP update is available now at the Microsoft Download Site
The Windows 2003 Server update is available at the Microsoft Download Site
Additional information is available at Microsoft KB Article 928388

Note: Updates are not available for previous version of Windows XP, customers should update to XP Service Pack 2 (SP2) and then apply the update for DST.

Once you have applied the Windows XP (SP2) update, you should update any applications that may also be affected by the update to Daylight Saving Time. Important Note: If you are running Outlook 2003, you must run the Outlook Time Zone Data Update tool

For more information see Microsoft's web site at http://www.microsoft.com/windows/timezone/dst2007.mspx

Microsoft Windows 2000

Microsoft Windows 2000 is no longer fully supported by Microsoft. Updates for Daylight Saving Time are only available under Microsoft's Extended Hotfix Support.

Update: ITS has made this hotfix available to the UI community here. (Log in with your domain\hawkid and password to download the hotfix.)

For more information see Microsoft's web site at http://www.microsoft.com/windows/timezone/dst2007.mspx

Mac OS 10.3.9 or later

Mac OS X Tiger update is available at http://www.apple.com/support/downloads/daylightsavingtimeupdatetiger.html

Requires 10.4.8
Apple released this new update that includes updated daylight saving times for more countries around the world.

Mac OS X Panther update is avaialble at http://www.apple.com/support/downloads/daylightsavingtimeupdatepanther.html

Requires 10.3.9

Mac OS 10.3.8 or earlier

Apple Mac OS 10.3.8 or earlier can either be updated to Mac OS 10.3.9 or later (and install the update listed above) in order to be aware of the changes to daylight saving time or the time zone can manually be changed.

For versions earlier than OS 10.3.9, you must manually change the time once Daylight Saving Time goes into effect by following these step:

Go to the Apple menu, select System Preferences, click Date & Time, then click the Date & Time tab. Then either drag the clock to the correct time or click the up and down arrows for the correct time. Make sure Set date & time automatically checkbox is unchecked.
OS9 users will need to go the Apple menu, select Control Panel, then select Date & Time and change the time manually from there.

Note: Customers who change their time manually will need to do so 4 times a year:

Once on the Second Sunday in March
Once on the First Sunday in April (because your computer will automatically adjust your time because it thinks daylight saving time is just starting - so you clock would be off by 2 hours)
Once on the Last Sunday of October (because your computer will again adjust automatically even though daylight saving time has ended yet)
Once on the First Sunday of November

Outlook 2007

Microsoft Outlook 2007 is aware of the changes to daylight saving time and no updates are required. Microsoft does recommend that customers do run the Outlook Time Zone Data Update tool.

Note: If Outlook 2007 is installed on Windows XP (SP2), the Windows XP Update for daylight saving time must be installed prior to running the Outlook Time Zone Data Update tool. See the Windows XP (SP2) section of this document for details.

Outlook Time Zone Update tool is available at the Microsoft Download Site
See 2007 Daylight Saving Time FAQ for additional information on the Outlook Time Zone Data Update tool.
Additional information on the Outlook Time Zone Update tool is available at Microsoft KB Article 931667
Additional information on preparing Outlook for daylight saving time is available at Microsoft's "Prepare Outlook calendar items for daylight saving time changes in 2007"

For more information see Microsoft's web site at http://www.microsoft.com/windows/timezone/dst2007.mspx

Outlook 2003

Customers running Outlook 2003 will need to run the Outlook Time Zone Data Update tool.

Note: If Outlook 2003 is installed on Windows XP (SP2) or earlier, the Windows Update for daylight saving time must be installed prior to running the Outlook Time Zone Data Update tool. See the Windows XP (SP2) section of this document for details on updating Windows XP machines.

Outlook Time Zone Update tool is available at the Microsoft Download Site
See 2007 Daylight Saving Time FAQ for additional information on the Outlook Time Zone Data Update tool.
Additional information on the Outlook Time Zone Data Update tool is available at Microsoft KB Article 931667
Additional information on preparing Outlook for daylight saving time is available at Microsoft's "Prepare Outlook calendar items for daylight saving time changes in 2007"

Entourage 2004

Entourage 2004 should have the Microsoft Office Update 2004 11.3.3 (or later) update installed.

Visit Microsoft Office Update 2004 11.3.3 site to download the update

Note: Entourage uses should also run the Outlook Time Zone Data Update tool. See our FAQ for details.

Windows CE and Windows Mobile Devices

For information on how to update Windows Mobile and Windows CE devices, click on a link below.

Windows CE - http://support.microsoft.com/?id=923027
Windows Mobile - http://www.microsoft.com/windowsmobile/daylightsaving/

Exchange Calendar Guidelines

Guidelines for handling the Daylight Savings Time issue with Exchange calendars (including public folders, resources, shared accounts and individual user accounts) can be found here: http://cs.its.uiowa.edu/exchange/calendardstguidelines.shtml

Microsoft

More information about Microsoft's time zone changes in general can be found here: http://www.microsoft.com/windows/timezone/dst2007.mspx

Unix/Linux

If you are running a distribution of Unix, you should look for updates from that distribution’s web site. See the ITS Help Desk Linux Support Center for links to distributions of Linux.

Java Platform

Applications running older Java Runtime Environments may need updates. More information and updates can be found here:
http://java.sun.com/developer/technicalArticles/Intl/USDST/

Links to Additional Vendor Sites

A web site called EdgeBlog has links to additional vendor web site pages about the daylight saving time changes.

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Last Updated: 04/24/2009