Correcting Daylight Savings Time on Windows

Correcting Daylight Savings Time on Windows XP

Why is your Windows computer setting the wrong time? It could be a failing CMOS battery, which keeps the time in your computer case. The battery is usually a CR2032 or similar. Otherwise, If you don’t have automatic updates turned on or you have a non-internet connected Windows PC, it may be setting the time according to the old daylight savings rules.

The Energy Policy Act of 2005 changed the official start and end dates for daylight savings time in most of the United States. This also extended daylight savings (i.e. fake time) through November instead of ending in October as it had previously.  One reason given for the change was to allow more daylight for Halloween trick-or-treating. Yet another example of ruining a long held tradition through legislation. It’s Halloween. It’s supposed to be dark and spooky. Why not require portable floodlights to be placed on every neighborhood street to offer more light for trick-or-treaters?

Of course the Energy Policy Act of 2005 was meant to save energy as well. Weather any actual energy was saved is debatable. Starting in 2007, the bill amended the Uniform Time Act of 1966 by changing the start and end dates of daylight saving time. Clocks were set ahead one hour on the second Sunday of March (March 11, 2007) instead of on the first Sunday of April (April 1, 2007). Clocks were set back one hour on the first Sunday in November (November 4, 2007), instead of the last Sunday of October (October 28, 2007).

To cope with these changes and the effect it has had on computer operating systems, Microsoft has come up with some updates for the different Windows versions.

Installing the correct update for your OS will enable your computer to automatically adjust the computer clock on the correct date due to the revised Daylight Saving Time.

For Windows XP Service Pack 3:

Download the Update for Windows XP SP3 (KB2570791) package.

Microsoft Knowledge Base page:


Year Date DST Begins Date DST Ends
2012 March 11 November 4
2013 March 10 November 3
2014 March 9 November 2
2015 March 8 November 1
2016 March 13 November 6
2017 March 12 November 5
2018 March 11 November 4
2019 March 10 November 3
2020 March 8 November 1
2021 March 14 November 7
2022 March 13 November 6
2023 March 12 November 5
2024 March 10 November 3
2025 March 9 November 2