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Configure Daylight Saving Time
http://www.vistaarticles.com/articles/188/1/Configure-Daylight-Saving-Time
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Published on 12/9/2006
 
Because of the Energy Policy Act, daylight saving time is extended by four weeks in 2007.

Configure Daylight Saving Time

The 2006 implementation is as follows:

Daylight saving time starts at 02:00 A.M. on April 2, 2006.
Daylight saving time ends at 02:00 A.M. on October 29, 2006.

The 2007 implementation is as follows:

Daylight saving time starts at 02:00 A.M. on March 11, 2007.
Daylight saving time ends at 02:00 A.M. on November 4, 2007.

 Manually configure daylight saving time dates

You can manually modify time zone settings by using the Tzedit.exe utility. Use this method if you have to configure daylight saving time dates on no more than several computers. To do this, follow these steps:

1. Start Time Zone Editor.
2. In the Time Zones list, select a time zone, and then click Edit. For example, click (GMT-08:00) Pacific Time (US & Canada); Tijuana, and then click Edit.
3. In the Edit Time Zone dialog box, click to select the Automatically set Daylight Saving Time check box.
4. Specify the correct daylight saving time start and end dates. To do this, follow these steps:a.  In the Start Day box, click the number of the day, the corresponding day of the week, and the month that you want. For example, click Second, click Sunday, and then click October.
b.  Select the time that you want to start daylight saving time. For example, select 12:00 AM.
c.  In the Last Day box, click the number of the day, the corresponding day of the week, and the month that you want. For example, click Last, click Sunday, and then click February. 
d.  Select the time that you want to end daylight saving time. For example, select 12:00 AM.
e.  In the Daylight Bias list, select how long you want the time to change when daylight saving time is in effect. For example, to set the clock forward 1 hour, leave the default setting of +1:00.
f.  Click OK, and then click Close.
g.  Click Start, point to Settings, point to Control Panel, and then double-click Date/Time.
h.  Click the Time Zone tab.
i.  Select a different time zone than the (GMT-08:00) Pacific Time (US & Canada); Tijuana time zone, and then click Apply.
j.  Click (GMT-08:00) Pacific Time (US & Canada); Tijuana, and then click OK.

Note Steps i and j are required for the new changes to take effect.