Microsoft Windows
The time zone database in most Windows-based computer systems stores only a single start and end rule for each zone, and daylight saving information is stored in the registry key HKEY_LOCAL_MACHINESOFTWAREMicrosoftWindows NTCurrentVersionTime Zones, under the TZI registry value. (In Windows XP and Windows 2003, timezone information is stored in the registry key HKEY_LOCAL_MACHINESYSTEMCurrentControlSetControlTimeZoneInformation). For example, DST ends on the last Sunday in October, regardless of year. When the rule changes (e.g. Israeli DST ending almost one mount earlier than United States), an update needs to be applied. In the case of a single-year anomaly, a new time zone is created and used. Before the following year, the time zone will have to be switched back to the original. For permanent rule changes, the rule definition for the time zone can be changed without requiring a new time zone to be set up.
One of the problems of this approach is that software that uses time zone information will get incorrect results if referring to a year with rules that are different from those currently in the database. Microsoft did not modify the start and end rule for the time zones affected, but instead added new timezones with the words “(Commonwealth Games)”which caused various issues with many software applications, including Ms Outlook and several accounting packages. Workarounds for the issue were to use the Microsoft utility timezone to modify the start and finish of each affected timezone, then either reboot the computer or go into Date and Time in the Control Panel, click on the Time Zone tab and click on OK to force Windows to refresh its daylight saving time information.
Utilities and more info you can find in:
http://www.petri.co.il/summer_clock_in_israel_for_2006.htm
http://regevnet.dyndns.org/ the site is in Hebrew
The start and stop dates for Daylight Saving Time (IDT) for 2002 – 2009 are:
Year
|
Start
|
End
|
| 2002
|
Mar 29
|
Oct 7
|
| 2003
|
Mar 28
|
Oct 3
|
| 2004
|
Apr 7
|
Sep 22
|
| 2005
|
Apr 1
|
Oct 9
|
| 2006
|
Mar 31
|
Oct 1
|
| 2007
|
Mar 30
|
Sep 16*
|
| 2008
|
Mar 28
|
Oct 5
|
| 2009
|
Mar 27
|
Sep 27
|




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