This update describes changes the time zone data to accommodate daylight saving time (DST) changes in several countries. Also includes other DST-related changes, time zone-related changes, and settings-related changes, and is a cumulative update rollup that includes all changes that were previously released in Microsoft Knowledge Base articles 928388, 929120, 933360, 942763, 951072, 955839 and 970653. Note When you apply this update, you may receive: Update cannot be installed as a newer or same time zone update has already been installed on the system, indicating that you’ve already applied correct update, and No additional action is required to update Windows operating system software.

Download: Windows 7 (KB976098) x86, x64 | Windows Server 2008 R2 (KB976098) x64, Itanium-based Systems

More info: KB976098