The government of Brazil has announced a new time zone start date and end date for Brazil for the period of 2007 through 2008. The new time zone information is as follows:

• Daylight saving time starts October 19, 2008 (the third Sunday in October)
• Daylight saving time ends February 15, 2009 (the third Sunday in February)

Windows-based computers will not correctly interpret the time that is related to the transition to daylight saving time. The hotfix that is mentioned in this article addresses this time zone change. This hotfix updates the (GMT-3:00) Brasilia time zone and the (GMT-4:00) Manaus time zone to use the new time zone information for 2008 through 2009.

This article describes a hotfix that is available for users of the following components:

• Windows Service for UNIX
• Utilities and SDK for Subsystem for UNIX-based Applications (SUA)

This hotfix incorporates daylight saving time (DST) changes in Argentina, in Chile, in Egypt, in Iran, in Iraq, and in Israel.

The government of Egypt has announced a new daylight saving time end date for Egypt for the year 2008. The new time zone information is as follows:

• Daylight saving time starts at 23:59:59 on the last Thursday of April 2008.
• Daylight saving time ends at 23:59:59 on the last Thursday of August 2008.

A hotfix is available to update the daylight saving time for the (GMT+02:00) Cairo time zone for Windows Vista-based, Windows Server 2008-based, Windows XP-based, and Windows Server 2003-based computers.

The government of Egypt has announced a new time zone end date for Egypt for the period of 2008. The new time zone information is as follows:

• Daylight saving time starts at 23:59:59 on the last Thursday of April, 2008.
• Daylight saving time ends at 23:59:59 on the last Thursday of August, 2008.

The unattended DisableAutoDaylightTimeSet setting has no effect when you set the setting to true on a Windows Vista-based computer. This behavior occurs when the time zone that is used by the computer has dynamic daylight saving time (DST) endpoints. For example, this setting has no effect in the United States.

Microsoft has learned of a possible change in the observance of daylight saving time in Iraq that could affect customers who use the “(GMT +03:00) Baghdad” time zone. (This is also known as the Arabic time zone.) We have unofficial reports that the Ministry of Iraq has decided that the country will no longer observe daylight saving time. Daylight saving time has historically taken effect in Iraq on April 1 and has continued through October 1. Currently, it seems that this change is likely. However, this information could be reversed at any time.

On April 1, 2008, Windows-based computers that are configured to use the “(GMT +03:00) Baghdad” time zone will automatically transition to daylight saving time despite the expected change in Iraq’s daylight saving time policy. However, the hotfix that is described in the “More information” section updates the “(GMT +03:00) Baghdad” time zone in compliance with this expected policy change, beginning April 1, 2008.

For more information about time zone changes in Windows, click the following article number to view the article in the Microsoft Knowledge Base:

942763 December 2007 cumulative time zone update for Microsoft Windows operating systems

The update that this article describes changes the time zone data to accommodate daylight saving time (DST) changes in several countries, as outlined in this article. This update also includes other DST-related changes, time zone-related changes, and settings-related changes. Some of these changes have occurred since the products that are listed in the “Applies to” section were originally released.

The update that this article describes is a cumulative update rollup that includes all the changes that were previously released in Microsoft Knowledge Base (KB) articles 928388, 929120, and 933360.

Important: This update supersedes and replaces update 933360, which was released in August 2007. This update also includes additional time zone changes that were signed in to law after update 933360 was created.

If you have already deployed update 933360, read the descriptions of the specific time zone changes that are addressed in this Microsoft Knowledge Base (KB) article to determine whether you must deploy this update immediately. If systems are not directly affected, you can schedule deployment at the next available opportunity.

We recommend that you deploy the most current Windows cumulative time zone update to guarantee the consistency of the time zone database on all systems.

Important: Before you apply the update that is described in this article, be aware of potential issues that may affect Microsoft Outlook. For more information about these issues, click the following article number to view the article in the Microsoft Knowledge Base:

931667 How to address the daylight saving time changes in 2007 by using the Time Zone Data Update Tool for Microsoft Office Outlook

Important:

• If you are running Microsoft Exchange Server in an Information Technology (IT) environment, you must take additional measures to guarantee the correct operation of Exchange Server. For more information about the Exchange daylight saving time (DST) update, click the following article number to view the article in the Microsoft Knowledge Base:
  

  941018 How to address daylight saving time by using the Exchange Calendar Update Tool

• Cumulative time zone updates contain only data that has changed for a specific region or that has been added to maintain parity with other operating system versions. Therefore, if a time zone key has been deleted, some original values may not be restored after you apply the cumulative zone update.

We do not recommend that you delete any registry keys that are related to time zones. On a computer that has incomplete time zone keys, first restore the time zone keys from a known good backup. Then, apply the update.

An update for DST changes in 2007 is now available for computers that are running Subsystem for UNIX-based Applications (SUA) in Windows Vista.

Note: Subsystem for UNIX-based Applications is available in the following versions of Windows Vista:

• Windows Vista Ultimate
• Windows Vista Enterprise

Consider the following scenario. You take the following actions on a computer that is running Microsoft Windows XP or Microsoft Windows Server 2003:

1. You install the 2007 time zone update for Microsoft Windows operating systems that is documented in the following Microsoft Knowledge Base article:
   928388 2007 time zone update for Microsoft Windows operating systems
2. You install the C run-time (CRT) update that is documented in the following Microsoft Knowledge Base article:
   932590 FIX: Windows-based applications that use the TZ environment variable may not work as expected because of changes to DST
3. You set the TZ environment variable.

In this scenario, when you create a custom application that uses the JScript version 5.7 Date object, the time is reported incorrectly for dates that are between the second Sunday in March and the first Sunday in April for the year 2007. Instead of the time being reported in daylight saving time, the time is reported in standard time. For example, for March 30, 2007, the JScript Date object reports time in standard time instead of in daylight saving time.

Note: JScript version 5.7 is included with Windows Vista. Additionally, when you install Internet Explorer 7 on a computer that is running Windows XP with Service Pack 2 (SP2), Windows XP Professional x64 Edition, or Windows Server 2003 SP1, JScript version 5.7 is installed.

The government of Brazil has announced a new time zone start date and end date for Brazil for the period of 2007 through 2008. The new time zone information is as follows:

• Daylight saving time starts October 14, 2007 (Second Sunday in October)
• Daylight saving time ends February 16, 2008 (Third Sunday in February)

Windows-based computers will not correctly interpret the time that is related to the transition to daylight saving time. The hotfix that is mentioned in this article addresses this time zone change. This hotfix updates the (GMT-3:00) Brasilia time zone and the (GMT-4:00) Manaus time zone to use the new time zone information for 2007 through 2008.