Important Updates are available on Windows Update and on Microsoft Update that enable Windows to correctly apply the changes for daylight saving time (DST) 2007 and later. After these updates are applied, Windows correctly calculates the current offsets from UTC time to local time on the computer when DST occurs. The offsets include the offsets for the base APIs and for the networking time-related APIs.
For more information about the DTS in Windows, click the following article number to view the article in the Microsoft Knowledge Base:
2007 time zone update for Windows XP and Windows Server 2003