Hot Topics for Daylight Saving Time changes

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Notice: Hotfix Available for Egypt and Western Australia 2009 Daylight Saving Time

(Posted 2009-08-07)

Egypt has announced to change the Daylight Saving Time (DST) to end on midnight August 21st. This hotfix updates the end date of DST for the "(GMT+02:00) Cairo" time zone in 2009. The clock will move one hour backward at midnight between August 20th and August 21st.

Australia has announced the end of Daylight Saving Time for the Western Australia time zone. This hotfix removes the Daylight Saving Time for the "(GMT+08:00) Perth" time zone. More specifically, this hotfix:

  • Sets DST end date for Egypt at 23:59:59.999 on August 20th, 2009
  • Removes DST for Western Australia time zone
Microsoft has produced a hotfix to implement this change. If interested in downloading this hotfix, please refer to KB 974176 titled: "A hotfix is available to update the Daylight Saving Time for the "(GMT+02:00) Cairo" and "(GMT+08:00) Perth" time zones for the year 2009 for Windows Server 2003-based, Windows Vista-based, Windows Server 2008-based, and Windows 7-based computers."

Notice: Microsoft Windows Daylight Saving Time and Time Zone update now available (August 2009)

The most recent cumulative update to daylight saving time (DST) and world time zones (TZ) is now available for supported versions of the Windows operating system via Microsoft Download Center and Windows Update.

Microsoft product teams follow a semi-annual DST and TZ update schedule, which follows the Windows regular schedule for publishing newly legislated DST rules and time zone updates. These annual Windows "Cumulative Daylight Saving Time and Time Zone Updates" are released in December for each calendar year; a semi-annual update will be released in August, as needed. Microsoft products that are affected may also schedule updates to accommodate some of these changes.

For more information about this cumulative DST and TZ update, visit the following Microsoft Web site: http://support.microsoft.com/kb/970653.

Notice: Optional Fix-it Available for Bangladesh 2009 Daylight Saving Time

As reported in the Bangladesh Government’s Gazette, Bangladesh has announced the introduction of Daylight Saving Time (DST). The start of DST for 2009 is on June 19th at 11:00 PM.

Microsoft has produced an automated workaround (called a fix-it) to implement the DST Start time change for Windows XP, Windows Server 2003, Windows Vista and Windows Server 2008. The Fix it solution is a MSI file so it is deployed as any other MSI based software package.

If interested in downloading this workaround please refer to KB 972423 titled: "An optional update is available to update the Daylight Saving Time for Bangladesh for the year 2009 for Windows XP, Windows Server 2003, Windows Vista and Windows Server 2008 based computers"

For other Windows versions, please refer to KB 914387 "How to configure daylight saving time for Microsoft Windows operating systems" on how to update the time zone registry key.

Notice: Hotfix Available for Morocco 2009 Daylight Savings Time

Morocco has announced the start of DST for 2009 on June 1st at midnight. The clock will move one hour forward at midnight between May 31st and June 1st, and then move one hour back at midnight between August 20th and August 21st in 2009. There was no DST for Morocco in 2009 prior to this update.More specifically, this update sets DST for Morocco as follows:
  • DST starts at 23:59:59 on May 31st, 2009
  • DST ends at 23:59:59 on August 20th, 2009

Microsoft has produced a hotfix to implement this change. If interested in downloading this hotfix, please refer to KB 970613 titled: "A hotfix is available to update the Daylight Saving Time for the "(GMT) Casablanca" time zone for the year 2009 for Windows XP-based, Windows Server 2003-based, Windows Vista-based and Windows Server 2008-based computers."

Notice: Now available for Windows XP and Windows Server 2003: Optional Hotfix Available for Pakistan 2009 Daylight Saving Time

As reported in various publications, including Daily Times, Pakistan has announced the start of DST for 2009 on April 15th at midnight. This information is subject to change as it has not been officially confirmed by a Pakistani government source.

Last Monday a hotfix was released to implement this change for Windows Vista and Windows Server 2008. The update is now also available for Windows XP and Windows Server 2003.

If you are interested in downloading this hotfix, please refer to KB 970084 titled: "A hotfix is available to update the Daylight Saving Time for the "(GMT +5:00) Islamabad, Karachi" time zone for the year 2009 for Windows Vista-based and Windows Server 2008-based computers".

Advisory: Tunisia Discontinues Daylight Saving Time in 2009

The Tunisian press agency reported that Daylight Saving Time(DST) will be discontinued in Tunisia in 2009 due to the fact that the fasting month of Ramadan coincides with the period concerned by summer time. No reports yet as to whether Tunisia will resume DST in 2010.

Tunisians can switch their computers to the "W. Central Africa Standard Time" time zone with a display name of "(GMT+01:00) West Central Africa". This time zone has a bias of UTC +1 which is Tunisia’s standard time bias and does not observe DST.

Microsoft's product teams are moving to a regular rhythm to update their products and services to reflect these time changes. For each update release, Microsoft accepts change requests at up to a few months prior to the release date. Please refer to Microsoft's Policy in Response to DST/TZ Requests, providing recommendations in order to achieve more seamless transitions to new DST and time zones policies. We suggest that governments should provide the following when considering changing DST or making adjustments to time zones:

  1. Ample advance notice (1 year or more) of the planned change.

  2. Official published confirmation of planned changes to DST or time zones.

  3. Concentrated efforts on promoting the change to the affected citizens.

Important note for governments: Please refer to Microsoft's Policy in Response to DST/TZ Requests. It's important for countries and territories to work towards seamless transitions to new DST and time zones policies, providing ample advance notice (of a year or more) with published confirmation of planned changes. In addition, we suggest that entities considering the changes consider implementing changes at the next clock tick after 01:59:59 rather than at 00:00:00. Making the change at midnight can impact daily systems, such as back ups, financial reports, data pulls or other automated tasks.

Advisory: Syria to Observe Daylight Saving Time starting March 26

The Syrian Arab News Agency (SANA) reported that daylight saving time in Syria will begin on March 26, 2009. NO reports yet as to when DST will end in Syria this year.

The report states that The Syrian Ministers approved the suggestion by the Ministry of Electricity to begin work with the daylight saving time on Friday March 27th, with clocks set ahead 60 minutes on the night of Thursday March 26th as noted here in English and here in Arabic.

Microsoft's product teams are moving to a regular rhythm to update their products and services to reflect these time changes. For each update release, Microsoft accepts change requests at up to a few months prior to the release date. Please refer to Microsoft's Policy in Response to DST/TZ Requests, providing recommendations in order to achieve more seamless transitions to new DST and time zones policies. We suggest that governments should provide the following when considering changing DST or making adjustments to time zones:

  1. Ample advance notice (1 year or more) of the planned change.

  2. Official published confirmation of planned changes to DST or time zones.

  3. Concentrated efforts on promoting the change to the affected citizens.

Important note for governments: Please refer to Microsoft's Policy in Response to DST/TZ Requests. It's important for countries and territories to work towards seamless transitions to new DST and time zones policies, providing ample advance notice (of a year or more) with published confirmation of planned changes. In addition, we suggest that entities considering the changes consider implementing changes at the next clock tick after 01:59:59 rather than at 00:00:00. Making the change at midnight can impact daily systems, such as back ups, financial reports, data pulls or other automated tasks.

Advisory: Palestine to Observe Daylight Saving Time starting March 26

Reports today via the Palestine News Network (arabic.pnn.ps) reported that daylight saving time in Palestine will begin on March 26, 2009, and end around September 27.

The report states that Palestinian officials have decided to begin daylight saving time on Thursday, March 26, 2009, and expects to maintain DST until September 27, 2009 as noted here (in Arabic).

Microsoft's product teams are moving to a regular rhythm to update their products and services to reflect these time changes. For each update release, Microsoft accepts change requests at up to a few months prior to the release date. Please refer to Microsoft's Policy in Response to DST/TZ Requests, providing recommendations in order to achieve more seamless transitions to new DST and time zones policies. We suggest that governments should provide the following when considering changing DST or making adjustments to time zones:

  1. Ample advance notice (1 year or more) of the planned change.

  2. Official published confirmation of planned changes to DST or time zones.

  3. Concentrated efforts on promoting the change to the affected citizens.

Important note for governments: Let me note that in support of these types of changes, we provide Microsoft's Policy in Response to DST/TZ Requests. It's important for countries and territories to work towards seamless transitions to new DST and time zones policies, providing ample advance notice (of a year or more) with published confirmation of planned changes. In addition, we suggest that entities considering the changes consider implementing changes at the next clock tick after 01:59:59 rather than at 00:00:00. Making the change at midnight can impact daily systems, such as back ups, financial reports, data pulls or other automated tasks.

Why daylight saving time (DST) updates are not included in service packs for versions of Windows that are earlier than Windows Vista

Summary:

DST updates are not included in service packs for versions of Windows that are earlier than Windows Vista. DST updates are not included to allow for certain auditing scenarios in which the existing date and time stamps may have to be accurately rendered by using the DST rules that were in effect when the date and time stamps were created. This may be important when you audit events that occurred before the change in to or out of DST.

Therefore, for all service packs for versions of Windows that are earlier than Windows Vista, you have to install DST updates separately so that you can uninstall them if you have to enable historical tracking of events. If the new rules are hard coded into a service pack and if computers are deployed with that service pack slipstreamed, you cannot apply an older set of DST rules for these auditing purposes.

More Information:

The Windows time APIs that were historically used to display time stamps did not account for DST rules. These Windows time APIs used the current system time offset to convert from Coordinated Universal Time (UTC) to local time.

This had the following visible effects when you looked at file time stamps in a folder or when you looked at e-mail time stamps in Microsoft Office Outlook:
  • If you were in standard (for example, winter) time and you looked at a file or e-mail time stamp that was created during DST (for example, summer), the file or e-mail time stamp was off by one hour (for example, as if DST did not exist). On the other hand, if you were in DST and you looked at a file or e-mail time stamp that was created during standard time, the file or e-mail time stamp was off by one hour in the opposite direction because the local DST offset was applied. This was a documented behavior in Windows.
  • If the DST start date and end date changed and you looked at a file or e-mail time stamp that was created during the “delta” period of an earlier year, the offset was incorrect. This issue occurred even if Windows or an application applied the current DST rules to determine standard time (winter) vs. DST (summer).

Scenarios that are affected by this issue involve auditing historical data. In some customer-specific environments, such as in healthcare, financial, or legal areas, you may have to display a historically correct local time for files, e-mail messages, event logs, or other data.

One way to do this accurately on systems that have updates installed is to uninstall the updates. Therefore, the correct time zone rules are the current DST time zone rules on the system at the time that the event occurred. Then, you can set the data appropriately (for example, DST or non-DST).

If the new rules had been hard coded into a service pack and if computers had been deployed with that service pack slipstreamed, there would have been no way to apply an older set of rules for these auditing purposes. This is why the new rules are not automatically included in service packs for versions of Windows that are earlier than Windows Vista. Instead, the current DST updates have to be applied directly to any newly built systems. For consumer systems, this occurs automatically through Windows Update.

This decision was made in early 2007 when Microsoft was developing the original 2007 DST time zone update packages for Windows and when there was no alternative method to display historically correct time stamps other than to uninstall the DST updates.

This issue became somewhat less critical with the Design Change Request that was implemented in hotfix 960417. This hotfix implements a historically accurate local time translation to two specific system functions and is documented in Microsoft Knowledge Base article 960417:

http://support.microsoft.com/kb/960417

Therefore, in Windows Vista Service Pack 1 and in later service packs, DST packages are included in the service packs. Windows Vista service packs and later versions of Windows will include the most-recent DST package that is available when they are created. Because DST packages are released bi-annually, you may still have to download a more recent DST package than the package that is included in a Windows Vista service pack.

Not all built-in Windows applications use these newly updated functions. However, these functions are available for third-party applications. These functions are useful in various types of applications. One example of this is a user auditing scenario in which the ability to use DST rules for previous years on a current Windows service pack is critical.

The functions that let applications accurately retrieve historically accurate time stamps are as follows:

  • SystemTimeToTzSpecificLocalTime: This function converts a time in UTC to a specified time zone's corresponding local time.
  • TzSpecificLocalTimeToSystemTime: This function converts a local time to a time in UTC.

Many other system functions still do not have the historical DST correction included. These include the following functions:

  • The GetSystemTime function and the GetSystemTimeAsFileTime function obtain the current UTC time in a SYSTEMTIME structure or in a FILETIME structure.
  • The GetLocalTime function obtains the current local time in a SYSTEMTIME structure.
  • The GetTimeZoneInformation function obtains a TIME_ZONE_INFORMATION structure that describes the current time zone and the DST setting for the computer.
  • The SystemTimeToFileTime function and the FileTimeToSystemTime function marshal between SYSTEMTIME structures and FILETIME structures.
  • The FileTimeToLocalFileTime function and the LocalFileTimeToFileTime function convert and translate a FILETIME structure between UTC and local time by using the current time zone and the DST setting on the computer.
  • The NetRemoteTOD function obtains the time from a remote server by using the server’s information and settings.
Microsoft Daylight Saving Time and Time Zone update now available (December 2008)

The most recent cumulative updates to daylight saving time (DST) and world time zones (TZ) are now available for supported versions of the following products. For the latest DST updates on each of these products, please visit Microsoft Daylight Saving Time Support page. The cumulative updates can be downloaded as indicated in the same Web page.

Microsoft product teams follow a semi-annual DST and TZ update schedule, which follows the Windows regular schedule for publishing newly legislated DST rules and time zone updates. These annual "Cumulative Daylight Saving Time and Time Zone Updates" will be released in December for the coming calendar year; a semi-annual update will be released in July/August, as needed. Microsoft products that are affected may also schedule updates to accommodate some of these changes.

For more information about all the DST and TZ updates that have been made to date, visit the following Microsoft Web site:

914387 - How to configure daylight saving time for Microsoft Windows operating systems

Daylight Saving Time and Time Zone update for Windows now available (revised December 2008)

The most recent cumulative updates to daylight saving time (DST) and world time zones (TZ) for Windows are now available for supported versions of the Windows operating system. The cumulative updates have been released to the Microsoft Download Center. These updates support versions of Windows XP, Windows Server 2003, Windows Vista, and Windows Server 2008. For information that details the changes in the cumulative updates, visit the following Microsoft Web site:

955839 - December 2008 cumulative time zone update for Microsoft Windows operating systems

The cumulative updates are also available on the Windows Update site beginning December 11, 2008, as part of the normal update process for Windows.

Consumers and small businesses may want to use Microsoft Update to download and install updates that are available from Windows Update or wait for the latest update to automatically install on your computer via Windows Automatic Update.

For more information about the service that is provided by Microsoft Update, visit the following Microsoft Web site:

http://www.microsoft.com/protect/computer/updates/mu.mspx

System administrators and IT professionals may download the latest packages for distribution to their users.

Microsoft product teams follow a semi-annual DST and TZ update schedule, which follows the Windows regular schedule for publishing newly legislated DST rules and time zone updates. These annual "Cumulative Daylight Saving Time and Time Zone Updates" will be released in November/December for the coming calendar year; a semi-annual update will be released in July/August, as needed. Other Microsoft products that are affected may also schedule updates to accommodate some of these changes. For the latest DST updates on each of these products, please visit the following Microsoft Web site:

http://support.microsoft.com/gp/dst_prodlist

For more information about all the DST and TZ updates that have been made to date, visit the following Microsoft Web site:

914387 - How to configure daylight saving time for Microsoft Windows operating systems

Daylight saving time ends this weekend, November 2, in much of North America (posted October 30, 2008)

Daylight saving time ends this weekend in much of North America. The US Energy Policy Act of 2005 introduced changes to the start dates and the end dates of DST beginning in 2007. Now, DST in North America is observed across most of the United States and Canada from the second Sunday in March through the first Sunday in November. In 2008, DST generally ends at 2:00 A.M. local time on Sunday, November 2. This results in a new DST period that is approximately three to four weeks longer than previous years.

Some parts of Canada and the United States do not observe DST. They remain on standard time throughout the year. This includes Arizona, Hawaii, American Samoa, Guam, Puerto Rico, the US Virgin Islands, Saskatchewan, and parts of northern British Columbia.

Pakistan: Daylight saving time ends on November 1 at midnight

Daylight saving time ends this weekend in Pakistan. Late in August 2008, it was announced that Pakistan's daylight saving time (DST) would be extended to midnight between October 31 and November 1, 2008.

In May of 2008, Pakistan introduced the observance of DST for the year 2008. Pakistan has not observed DST since the year 2002. Pakistan will use daylight saving time to save energy as it faces a power crisis. In 2008, the clocks will move one hour ahead (to UTC+6) at midnight between Friday, May 31 and Saturday, June 1. Later in the year, the DST end date was changed to October 31.

Daylight saving time is used to save energy by extending daylight. This helps reduce the need to use artificial lighting, air-conditioning, and other electrical appliances. In recent times, electricity supplies to homes, businesses, and factories across Pakistan were shut off for several hours a day.

Argentina Daylight Saving Time changes for 2008 and 2009 (revised October 17, 2008)

The Argentinean government has announced new start and end dates for the Daylight Saving Time in Argentina for the period of 2008-2009. The new daylight saving time for Argentina is the following:

  • Daylight saving time begins: October 19, 2008
  • Daylight saving time ends: March 15, 2009
Since the new dates published by the government are different from what was defined in the previous years, Windows-based computers will not correctly interpret the time that is related to the transition to daylight saving time. In addition to Microsoft products, other software, OS releases and hardware (phones, routers, switches and managed devices) may require updates and changes.

Our teams at Microsoft have taken several steps to alert customers and partners to the change in Argentina. Although there will not be any hot fixes provided prior to the change on Sunday, advice and recommendations have been provided and posted to http://support.microsoft.com/gp/dst_argentina20082009. More information is available at http://www.microsoft.com/argentina/dst.

Guidance for Mauritius on upcoming Daylight Saving Time implementation for 2008-2009

As noted at http://www.afrol.com/articles/29955 on July 23, 2008 and in L'Express newspaper, the government of Mauritius has decided to adopt Summer Time (as it is known in Europe, also known as daylight saving time) in the island nation of over 1 million. According to published government announcements, the country/region will begin recognizing Summer Time in October of this year. Official reports note that DST will begin on October 26, 2008 and end on March 27, 2009.

The post on our TechNet blog summarizes the actions that we recommend for customers in Mauritius to address the implementation of daylight saving time and to mitigate its impact. The TechNet blog post discusses the issues that are anticipated at the time this document was written, and the effects that customers may face are not restricted to those issues.

Windows hotfix available for Egypt 2008 Daylight Saving Time change

The government of Egypt announced that because of the observance of Ramadan, it has changed the end of Daylight Saving Time to midnight August 28, 2008.

Upon request, Microsoft has created out of band release packages for Windows Vista, Windows Server 2008, Windows XP, and Windows Server 2003 for the Egypt DST update.

For more information about this DST hotfix, refer to the following Microsoft Knowledge Base article:

953732 - A hotfix is available to update the daylight saving time for the "(GMT+02:00) Cairo" time zone for the year 2008 for Windows Vista-based, Windows Server 2008-based, Windows XP-based, and Windows Server 2003-based computers

To view or to request the hotfix download, click here.

Please note that these packages are call-in/request only packages, and they will not be released to the Microsoft Download Center or to Microsoft Update Services. These change will be included in the next DST Windows cumulative package release (December 2008) for all currently supported operating systems (Windows XP, Windows Server 2003, Windows Server 2008 and Windows Vista).

Brazil 2008-2009 Daylight Savings Time changes (revised October 1, 2008)

The government of Brazil announced a change in the observance of daylight saving time in the country. According to the details in the Ministry's Decree number 6558 of September 8, 2008, DST will start the third Sunday of October and then end generally on the third Sunday of February of the following year. As confirmed on Brazil's Ministry of Energy Web site, the Electric Power Sector Monitoring Committee (the Comitê de Monitoramento do Setor Elétrico, or CMSE) set the new dates for DST, which will begin on October 19, 2008, and end on February 15, 2009.

Upon request, Microsoft has created out of band release packages for Windows Vista, Windows Server 2008, Windows XP, and Windows Server 2003 for the Brazil DST update.

For more information about this DST hotfix, refer to the following Microsoft Knowledge Base article:

957201 - A hotfix is available to update the "(GMT-3:00) Brasilia" time zone and the "(GMT-4:00) Manaus" time zone for 2008 through 2009 in Windows XP, Windows Server 2003, Windows Vista and Windows Server 2008

To view or to request the hotfix download, click here.

Please note that these hotfix packages are call-in or request only packages and they will not be released to the Microsoft Download Center or to the Microsoft Update Services. These changes will be included in the next DST Windows cumulative package release (December 2008) for all currently supported operating systems (Windows XP, Windows Server 2003, Windows Server 2008, and Windows Vista).

For more information in Portuguese, please see the following Web sites:For more information in English, please see the following Web sites:

Daylight Saving Time and Time Zone update for Windows now available (revised August 12, 2008)

The most recent cumulative updates to daylight saving time (DST) and world time zones (TZ) for Windows are now available for supported versions of the Windows operating system. The cumulative updates have been released to the Microsoft Download Center. These updates support versions of Windows XP, Windows Server 2003, Windows Vista, and Windows Server 2008. For information that details the changes in the cumulative updates, visit the following Microsoft Web site:

955839 - December 2008 cumulative time zone update for Microsoft Windows operating systems

The cumulative updates are also available on the Windows Update site beginning August 12,2008, as part of the normal update process for Windows.

Consumers and small businesses may want to use Microsoft Update to download and install updates that are available from Windows Update or wait for the latest update to automatically install on your computer via Windows Automatic Update.

For more information about the service that is provided by Microsoft Update, visit the following Microsoft Web site:

http://www.microsoft.com/protect/computer/updates/mu.mspx

System administrators and IT professionals may download the latest packages for distribution to their users.

Microsoft product teams are moving to a semi-annual DST and TZ update schedule, which follows the Windows regular schedule for publishing newly legislated DST rules and time zone updates. These annual "Cumulative Daylight Saving Time and Time Zone Updates" will be released in November/December for the coming calendar year; a semi-annual update will be released in July/August, as needed. Other Microsoft products that are affected may also schedule updates to accommodate some of these changes. For the latest DST updates on each of these products, please visit the following Microsoft Web site:

http://support.microsoft.com/gp/dst_prodlist

For more information about all the DST and TZ updates that have been made to date, visit the following Microsoft Web site:

914387 - How to configure daylight saving time for Microsoft Windows operating systems

Daylight Saving Time changes in Morocco and Pakistan (revised May 19, 2008)

Microsoft has learned of a change to the observance of Daylight Saving Time (DST, aka regionally as Summer Time) in Morocco and Pakistan that could impact customers using local time zones. We have news that Morocco will switch from GMT to GMT+1:00 beginning on June 1, 2008, and that the Pakistan Government will change from GMT +5:00 to GMT +6:00 June 1, 2008, at 12 midnight (local time). These changes may impact customers and partners in the regions who use local time zones, including entities engaged in business in or with the region.

Unfortunately, due to the short notice provided for these late breaking changes, we do not expect that product groups will provide updates incorporating these changes. The Windows organization plans to include these updates in the next release of the 2008 Cumulative Time Zone Update for Windows, scheduled to release in July/August 2008.

For manual remediation of Microsoft Windows operating systems in mainstream support, Microsoft will provide an updating to the following DST and time zone manual update article with the changes for Morocco and Pakistan:

914387 How to configure daylight saving time for Microsoft Windows operating systems

Advisory: Potential changes to Daylight Saving Time in Iraq

Microsoft has learned of a change to the observance of Daylight Saving Time (DST) in Iraq that could impact customers using the Baghdad time zone which is also called the Arabic time zone (GMT +03:00). The Ministry of Iraq has decided that the country will no longer observe DST as they have in prior years, which has historically taken effect on April 1. This may impact customers and partners in the region who use the Baghdad time zone, including entities engaged in business in or with the region. Microsoft has created product updates and guidance to help customer adjust to this change.

Microsoft is recognizing this change and provides the guidance to customers and partners should they have systems that may be impacted by this change in Iraq, as noted on the Microsoft Daylight Saving Time & Time Zone FAQs Blog at http://blogs.technet.com/dst2007/archive/2008/03/25/advisory-potential-dst-change-in-iraq-technical-guidance.aspx.

US and Canadian Daylight Saving Time

US and Canadian Daylight Saving Time occurs March 9: DST now begins on the second Sunday of March (in 2008, March 9), several weeks earlier than in years prior to 2007. DST will end later than usual, on the first Sunday of November (in 2008, November 2); more details on the new DST start and end times can be found here). This results in a new DST period that is approximately three to four weeks longer than in previous years. Generally, customers should have applied and updated their client and server systems previously with the 2007 DST and TZ updates, and continued to install cumulative updates as released (such as the 2008 Cumulative Time Zone Update for Windows has as noted in KB article 942763). Please review the list of impacted Microsoft products at http://support.microsoft.com/gp/dst_prodlist for a list of updates.

Some customers may be impacted, such as those in South America that requested and installed a DST/TZ hotfix (as provided recently for Argentina); multinational companies with activities in these areas should consider applying the hotfix updates or following published guidance for utilizing an appropriate time zone.

Argentina: Changes to daylight saving time: December 30

The government of Argentina approved a new change to their observance of daylight saving time in the country effective this Sunday, December 30, 2007 at 12:00am to March 16th, 12:00 for Argentina. Information is also available via our Argentinean web site at http://www.microsoft.com/argentina/dst, "Instrumentación del próximo horario de verano para Argentina en 2007-2008." Customers and partners will find additional information on this change and manual remediation at http://blogs.technet.com/dst2007/archive/2007/12/29/argentina-122907.aspx.

Australia Eastern and Central 2008 Daylight Saving Changes

Australia Eastern (New South Wales, Victoria, Australian Capital Territory and Tasmania) and Central (South Australia) time zones will extend daylight saving and also harmonise start and end times commencing April 2008. From April 2008, daylight saving will end on the first Sunday in April and recommence on the first Sunday in October in all states. See the Australian Government Time web site for more information.

For a summary of the status of product updates, we recommend that customers review the information at http://technet.microsoft.com/en-au/bb887637.aspx. In most cases, customer will find that these changes have been addressed when the latest cumulative time zone update for Microsoft Windows operating systems was applied (released December, 2008, as noted in Microsoft Knowledge Base article 955839. Some of the updates are not specific to the Australia Eastern and Central changes and can be applied immediately; other products (for example Office Groove) require manual adjustment after application of the time zone update to the host Windows operating system.

2008 Cumulative Time Zone Update for Windows

The 2008 Cumulative Time Zone Update for Windows has been released to the Microsoft Download Center (DLC) for currently supported Windows OS versions (including Windows XP, Windows Server 2003 and Windows Vista.)

This update can be found in KB article 955839.

As noted previously, the annual 2008 Cumulative Time Zone Update for Windows sets the known, correct dates for 2008 (including 2008 changes for Australia, Brazil and other countries we know that have changed their observance of DST entry/exit dates or time zones in 2008). This early drop of the update allows IT professionals and sysadmins to test the installation and deployment of the cumulative update roll-ups prior to broad distribution. The update packages will be distributed to computers via Windows Update in early December (the second Tuesday, Dec 11.)

Guidance for consumers and unmanaged customers: Generally, consumers should allow for the updates to be installed on their computers via Windows Update rather than download and install these updates from the DLC.

Outlook 2007 Free/Busy information moved ahead by one hour in a mixed Exchange environment

Free/Busy information for Exchange 2003 users when viewed through the Exchange 2007 Availability Service and Microsoft Office Outlook 2007 is displayed as being moved ahead by one hour when viewed on a client that has a system time of November 4, 2007 at 2:00 A.M. or earlier. After November 4, 2007 all Free/Busy information displays correctly for Exchange 2003 users when viewed through the Exchange 2007 Availability Service and Outlook 2007. This is not true for appointments that occur after March 9, 2008. A hotfix is planned for Outlook to resolve this problem for future time changes. Microsoft Knowledge Base article 944374 will be used to document this issue.

Windows Mobile

Many changes in daylight saving time (DST) and time zones have occurred. Microsoft has been working closely with customers, partners, and other people in the industry to help ensure a smooth and seamless transition. Although updates have been made available for mobile devices running Windows Mobile software, some users may not have the information that they need or did not follow the steps that are required to apply those updates. The correct end date for DST for 2007 in North America is November 4, 2007. Mobile devices for users who did not update, may have experienced the "fall back" in North America on October 28. Some user's mobile devices and calendars may be one hour early for the following week, if the appropriate updates are not applied. We recommend that customers who have to update, follow the instructions on http://www.microsoft.com/windowsmobile/daylightsaving/default.mspx to update their devices.

Windows

Microsoft Windows operating systems KB article 955839 is the latest Windows Cumulative Time Zone Update available. KB 955839 will be issued as an "Update Rollup" and available via WSUS. To note, this Knowledge Base article replaces KB 951072. Customers who have updated with the previous Rollup (KB 951072) should carefully review KB 955839 in the section on “Updates from the previous cumulative Windows time zone update” and determine if this update is necessary for their environment. To see such updates in WSUS, go to "Update Classifications" and select "Change," then check "Update Rollups" and sync. The KB will be released to WSUS on November 27th, 2007.

Windows KB article 955839 was issued as an "Update Rollup" and is available via WSUS, replacing KB 951072. For customers using SMS 2003 and ITMU, the DST Update Rollup KB 951072 was superseded by KB 955839 in the wsusscn2.cab file – the catalog consumed by ITMU. As a result, KB 951072 update is no longer available for deployment via ITMU.

We encourage customers to run the latest cumulative DST update on their systems as a general rule. All clients that haven't had KB 951072 installed, will now only report that KB 955839 is applicable (due to the way WUA handles and reports superseded KBs) but the clients that have installed the previous update will still report it as installed.

In the event KB 951072 was only partially deployed for an environment and not all machines can be readily updated to KB 955839, several options are available, among them:

  • Build further collections of machines that do not yet have either update rollup applied, and target those machines with a new patch package which includes KB 955839.
  • Continue to roll out KB 951072 to the remainder of the environment using standard software distribution.
  • For more information see the SMS 2003 and ITMU section of this update.

After patching the suspect client machines, you may need to address Outlook calendar items that may be displayed incorrectly now that the Windows time zone definitions have been updated.

Venezuela announces 2007 Time Zone changes

Venezuelan time zone changes: The government of the Bolivarian Republic of Venezuela has announced a change to the time zone for the country, which to date has typically observed South America Western Standard Time. According to current official reports, the start date for new time zone is yet to be determined, but projected to occur on December 9th, 2007. When customers move their Windows clients to the new time zone, clocks will move backwards 30 minutes, from UTC -4:00 to UTC -4:30. This change begins at 2:59:59 PM local time on the start date. Clocks should be moved back to 2:30:00 PM rather than advancing to 3:00:00 AM. For more information, please see Microsoft Knowledge Base article 955839.

Generally, end users do not have to install these updates manually. Updates will be installed via Windows Update beginning on December 11, 2007 rather than downloading and installing these from the Microsoft Download Center. For end users who have their computers managed by a central administrator, please contact your IT administrator for infomration on how computers on your network will be updated.

For a Web log of the most common questions and answers about moving appointments from one time zone to another for Venezuela, visit the following Web site:

Correcting the Outlook/Exchange Calendars of affected users

Determine which machines/users were affected. This list will be used to create the input file for the Exchange Calendar Update Tool. To determine which users are affected you should identify new machines that were introduced into your environment after August and are not patched with KB 933360. You will need to associate a user with each machine. For each potentially affected user you should check their Calendar to ensure accuracy during the extended DST period.

Any Calendars that have appointments which are displayed incorrectly (example: appointments appear to be moved by one hour) during the extended DST period will need to either manually update their appointments so that they appear correctly. Alternatively you can use the Exchange Calendar Update Tool or the Outlook Calendar Update Tool to correct the appointments.

The decision for which Calendar Update Tool to use is typically determined by the number of users affected, the number of Calendar items affected and the amount of end user interaction that is acceptable. For instance, if there are a small number of users affected and a small number of Calendar items in each Calendar then having end users run the Outlook Calendar Update Tool or requesting that they manually drag and drop appointments to the correct time could be an acceptable solution.

Exchange Calendar Update Tool

If you chose to update the user Calendars with the Exchange Calendar Update Tool then after you have compiled the list of users you will then need to obtain their Legacy Exchange DN. You will then enter the user’s Legacy Exchange DN into a text file along with their mailbox servers Legacy Exchange DN and the users time zone. KB 941018 contains additional information about creating this file and running the Exchange Calendar Update Tool.

"Update affected users with the Exchange Calendar Update Tool using the "Only Update Recurring Meetings" Advanced Option in Exchange Calendar Update Configuration Tool which is documented in KB 941018. Please do not update all items in these calendars as you may inadvertently change the time of a single-instance item that is correct. Complete information on how to use the tool can be found here:

956399 August 2008 cumulative daylight saving time (DST) update for Exchange 2000
Information about obtaining user LegacyExchangeDN information can be found at:
324606 How to use Legacydn.exe to correct Exchange organization names or Administrative Group names in Exchange Server 2003 or in Exchange 2000 Server
Once all recurring items are updated, instruct users to manually correct any remaining items in Outlook that are 1-hour off.
  1. Print a copy of your calendar during the extended DST period for reference.
  2. Manually move meetings that you organized to the correct time.
  3. Send an update for the meeting that you moved to all attendees so that the attendees' calendar reflects the correct time.
  4. Manually move all single-instance appointments.
  5. Manually move all recurring appointments within the extended DST period.
Outlook Calendar Update Tool

If you choose to update the user Calendars with the Outlook Calendar Update Tool, then you should use the instructions in KB 931667 and have the users carefully select which appointments that they want to have rebased. They should pay attention to the appointments that occur from October 28, 2007 – November 4, 2007 to ensure the accuracy of those appointments. More information on the Outlook Calendar Update Tool is available at:

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

You may also experience discrepancies in Resource Accounts (Conference Rooms) with double bookings or incorrect times. If this occurs then meeting organizers can update the meetings for an available time and send an update to all attendees.

Users should synchronize mobile devices and any additional Outlook clients (i.e. laptops, home machines) after all changes are completed.

Sharepoint Services

Windows SharePoint Services 3.0 and Microsoft Office SharePoint Server customers should be aware of important fixes recently updated that should be installed, particularly those related to daylight saving time. You should install the updates listed in KB article 934525. Please visit the Microsoft Web page at http://support.microsoft.com/gp/dst_prodlist#WSS3 for more details.

SMS 2003 and ITMU (Inventory Tool for Microsoft Updates)

For customers using SMS 2003 and ITMU (Inventory Tool for Microsoft Updates):

KB 951072 DST Update Rollup was superseded by KB 955839 in the wsusscn2.cab file – the catalog consumed by ITMU and the Distribute Software Updates Wizard. As a result, KB 951072 update is no longer available for deployment via ITMU. We encourage customers to run the latest cumulative DST update on their systems as a general rule.

However in the event KB 951072 was only partially deployed for an environment and not all machines can be readily updated to KB 955839, several options are available, among them:

  • Build further collections of machines that do not yet have either update rollup applied, and target those machines with a new patch package which includes KB 955839.
  • Continue to roll out KB 951072 to the remainder of the environment using standard software distribution.

Collections can be based on queries of Add/Remove programs Hardware Inventory data, which is enabled by default in SMS 2003.

The relevant Display Names of the updates in question are below:

Windows Server 2003
951072 – Update for Windows Server 2003 (KB 951072)
955839 – Update for Windows Server 2003 (KB 955839)

Windows XP
951072 – Update for Windows XP (KB 951072)
955839 – Update for Windows XP (KB 955839)

DST instructional videos available

The Microsoft DST Team has put together a few videos to assist you in your DST remediation planning and execution. Click the links below to learn more about the Windows Cumulative Update and the Outlook and Exchange Time Zone Data Update Tools.

On-Demand (hosted by Channel9.MSDN.com)

Indiana announces 2007 Time Zone changes

Indiana time zone changes: Effective November 4th, the Indiana counties of Knox, Daviess, Martin, Pike, and Dubois will be moving from the Central time zone to Eastern time. These are five 5 counties in Indiana that did not move to Eastern last year when the rest of Indiana moved. We did not release an update for Indiana since directions are to change the time zone to Eastern from Central. For more information please see the following: http://www.microsoft.com/windows/timezone/indiana.mspx.

For a Web log of the most common questions and answers about moving appointments from one time zone to another for Indiana, visit the following Web site:

Blogs

For a Web log of the most common questions and answers about daylight saving time changes affecting Microsoft products, please visit the Technet DST Blog site.
Last Review : September 18, 2009

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