Microsoft released set of Daylight Saving updates back in December 2009. Time Zone changes since last MS update Argentina Standard Time: Removes DST for 2010 and later years. Central Brazilian Standard Time: Updates dynamic DST table. Changes DST end date for 2010. E. South America Standard Time: Updates dynamic DST table; Changes DST end date for 2010. Egypt Standard Time: Changes the DST end date for 2009. Changes the TZI for 2010. Georgian Standard Time: Read more