Time Zones Revisited

As a co-worker pointed out, Microsoft stores time zone information in two places,

  1. HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Time Zones
    this is where the time zone database is stored.
  2. HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\TimeZoneInformation
    this is the current time zone information is stored.
    ie. the time zone information Windows is using currently.
    HKEY_LOCAL_MACHINE_SYSTEM_CurrentControlSet_Control_TimeZoneInformation

Simple once you know.  And you do need to know this, if you are ever unfortunate to have to deal with Daylight Savings changes.

References:
How to configure daylight saving time for Microsoft Windows operating systems
How to tell what Microsoft Time Zone you have