In August 2005, the United States Congress passed the Energy Policy Act, which changes the start and end of daylight saving time (DST) as observed in the United States. Some additional countries/regions are following the U.S. change.
As a result, DST started on March 11, 2007, which was three weeks earlier than previous years. DST will end on November 4, 2007, one week later than previous years.
To ensure that your Microsoft products are updated for the extended DST periods, Microsoft has prepared an update guide to assist you.
For all Microsoft products, see the Daylight Saving Time Help and Support Center at http://support.microsoft.com/DST2007.