Help      |      Chebucto Home      |      News      |      Contact Us     

102. DST: The time is a-changing

By Andrew D. Wright

On March 11, 2007 at 2:00 AM, Daylight Saving Time will begin three weeks earlier than usual. We'll just lose an hour of sleep but our devices are less flexible than we are and some of them are going to have problems.

Daylight Saving Time was a product of World War I designed to conserve energy. By having workers' shifts adjust to follow the seasonally changing daylight hours, less electrical energy was needed for lighting.

Locally it's been traditional for clocks to spring forward one hour on the first Sunday in April and fall back one hour on the last Sunday in October. With the passing of the U.S. Energy Policy Act of 2005 this changes to the second Sunday in March for clocks to move forward and first Sunday in November for them to shift back. Canada has adopted this policy as well.

Business users should be wary of the DST changes to time zones they deal with and double check appointment times for meetings scheduled between March 11 and April 1, 2007 and between October 28 and November 4, 2007.

Any device that uses time and dates such as calendar software, handheld planners, or programs that do time/date calculations can be affected by the DST change. Consult the device or software maker's web site for information and updates.

The new Microsoft Windows Vista operating system has the DST changes already in place and will automatically adjust the computer clock at the right time for most users.

Newfoundland and Labrador Windows users will need to adjust their computer time manually in all Windows versions including Vista. The automatic DST adjustment is using the old incorrect dates and should be turned off. Microsoft does have a registry edit online to put in the correct automatic DST settings for Newfoundland and Labrador but this has to be entered manually using regedit.

Windows XP (all varieties) and Windows Server 2003 users can download a system update from Microsoft. This update is listed as optional on the Windows Update site at the time of this writing but is supposed to be added to February's monthly critical updates and delivered automatically to Windows users with Automatic Updates turned on.

Users of earlier versions of Windows like Windows 2000, Windows ME, Windows 98 and Windows 95 can either turn off the automatic DST time correction and reset the computer clock by hand, or manually edit the Windows registry to fix the automatic DST adjustment.

Microsoft has a website listing all affected supported Microsoft programs that need to be adjusted or patched. Users of Microsoft Outlook in particular should be aware of the available patches.

Canadian Apple Macintosh users may also need to do some setup on their computers so they will correctly adjust the time on the right dates.

Other operating systems such as Sun's Solaris and the various varieties of Linux will also need to be patched.


National Research Council of Canada Official Time:


Microsoft DST changes site:


Microsoft Operating System DST updates:


How to manually adjust Microsoft computers:


Apple Macintosh information:


*nix (Unix, Linux, etc.) DST data:


The Mousepad runs every two weeks. It's a service of Chebucto Community Net, a community-owned Internet provider. If you have a question about computing, email or click here. If we use your question in a column, we'll send you a free mousepad.


The Mousepad Index


Originally published 11 February 2007


Our community is online here!


A feature of the Halifax Herald