SHL: Daylight Saving Time


DAYLIGHT SAVING TIME



Description:  Daylight Saving Time implementation varies from country to country.  Some countries may not observe daylight saving time, whereas other countries may change the start dates and end dates for daylight saving time every year. This can cause administrative confusion with DST updates and possible time issues on machines.


Microsoft strongly recommends that DST and time zone updates be installed on all affected systems, devices and applications to ensure consistency with current DST rules and time zone settings worldwide.


Customers should review the product updates available at http://support.microsoft.com/gp/dst_prodlist  for the latest updated information on Microsoft products affected by daylight saving time.


 


Scoping the Issue:  For issues regarding DST and the operating system, we should always verify that the latest DST Cumulative update has been installed. See Microsoft KB 955839 for the December 2008 Cumulative Update


Customers that have machines in regions outside those covered by the DST cumulative update packages can update the time zone by using registry files per Microsoft KB 914387.


 


Data Gathering:  In all instances, collecting either MPS Reports with the General, Internet and Networking, Business Networks and Server Components diagnostics, or a Performance-oriented MSDT manifest must be done.  You should also verify that the latest DST cumulative update has been applied.  Additional data required may include the following:



  • Collect the KB95839.log file and the TZLog.log file (this file is located in the %systemroot%\System32 folder)

  • Backup and export the following registry keys: 


    • HKLM\SYSTEM\CurrentControlSet\Control\TimeZoneInformation

    • HKLM\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Time Zones

 


Additional Resources: