Microsoft Daylight Saving Time & Time Zone Blog

Advisory: Bangladesh decides to end daylight saving time on December 31, 2009

On Monday, December 28, 2009 the Bangladesh government announced that, following a cabinet decision last week, the clocks would move back one hour to standard time at 11:59 PM on Dec 31.  The decision was also reported on The Daily Star.

A notice from the power ministry on Sunday, however, clarified that clocks would be set back again one minute before midnight on Dec 31.

The notice also stated that the government has decided to continue with Daylight Saving Time from 2010 to ensure maximum utility of daylight.
Clocks will be advanced to 11:59pm (GMT+7) from 10:59 pm on March 31, to continue until Oct 31.
They will be turned back to 10:59pm (GMT+6) from 11:59 pm on Oct 31, to run until March 31.

This communication only addresses recommendations for the Dec 31, 2009 change.  Microsoft will communicate future guidance for the 2010 DST transitions.

Users on all Windows OS platforms can switch their computers to the Central Asia Standard Time (Display name: (GMT+06:00) Astana.   For users that did not apply KB978125, the time zone display name will look like this: (GMT+06:00) Astana, Dhaka).

Alternatively, for Windows OS versions released earlier than Vista, users may opt to update the registry key manually if they previously applied KB978125.  Please note that the registry key value will be different if this operation is performed before Jan 1, 2010 than if it is performed after the start of the New Year, 2010.   The reason for this is that the registry key value is different in 2009 than it is in 2010.  Details on how to perform this operation can be found below in the section titled: “Manual Method to Perform DST Changes on down level platforms from Vista”.

Microsoft's product teams have moved to a regular rhythm to update their products and services to reflect 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 notes 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.
• We suggest that entities planning DST 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.

Manual Method to Perform DST Changes on down level platforms from Vista.

Prepare three files based on the source outlined below:

BanglaTZUpdate.reg
This will be the Time Zone update registry file.  It will change the time zone and DST setting for Bangladesh, and should not be altered in any way.  A pre-requisite of pursuing this option is to have the “Bangladesh Standard Time” time zone already defined in the Registry.

Users updating the registry key in 2009 must use the following value for the registry key:

Users updating the registry key in 2010 must use the following value for the registry key:

refreshTZinfo_Bangla.vbs
The DST and time zone settings  registry must be updated in two locations to become active. Importing the BanglaTZUpdate.reg file updates the time zone database in the registry and is the first step required. You must then update the TimeZoneInformation registry key in the <current control set> key.

The following script will identify the current time zone of the client computer and then reload the TimeZoneInformation registry key with the updated information from the time zone database.

The script contains some logging, as it writes an event to the Application log of the client computer where the script was run to report the status of the installation - Event ID 1 is reported when there was some form of failure, or Event ID 4 is reported on success.  You may modify or extend this script as you see fit to perform any additional logging or reporting you require.  

Note: Microsoft provides programming examples for illustration only, without warranty either expressed or implied. This includes, but is not limited to, the implied warranties of merchantability or fitness for a particular purpose.

BanglaTZUpdate.cmd
This is a batch file that will execute the above scripts sequentially. This will most likely be used in environments that require an automated deployment methodology across multiple machines, such as Group Policy.  It states the location of the above files is \\contoso.com\NETLOGON\ which should be updated to reflect your own environment.

Deploying the manual update on a single computer

To deploy the update on a single computer, create or copy the first two files from above to an accessible location.  Double-click on the .reg file, and then double-click on the .vbs script, to add the new time zone information to the registry and make it active. The DST settings will be changed.

Deploying the manual update on multiple computers

The following steps will assist guiding you in deploying the update to multiple computers using Group Policy Objects.  These steps outline the basic approach to take, but all actions should be carried out in accordance with your established standards and change management practices.  For other environments, you can use the scripts provided earlier and an installation/execution method of your choosing.

1.       Decide an appropriate location to contain the script files within your Netlogon folder of the domain controller that holds the PDC emulator role in the domain. 

2.       Ensure the BanglaTZUpdate.cmd file contains the full path to both the .reg file and the .vbs file as decided in Step 1.

3.       Copy the following files to the chosen location:

·         BanglaTZUpdate.reg

·         refreshTZinfo_Bangla.vbs

·         BanglaTZUpdate.cmd

4.       Wait until Active Directory replication occurs and the files and folders in the system volume (SYSVOL) shared folder replicate to all domain controllers in the domain.

5.       Click Start, click Run, type ‘control admintools’, and then click OK.

6.       Double-click Active Directory Users and Computers.

7.       Select an OU that contains the computers that you want to apply this script to. In this example, we will use an OU that is named DST_Bangla. This example also assumes that this OU contains only computer accounts.

8.       Right-click the DST_Bangla OU, and then click Properties.

9.       Click the Group Policy tab, click New, type Bangla DST Registry Update, and then press ENTER.

10.   Click Edit. The Group Policy Object Editor tool starts.

11.   Expand Computer Configuration, expand Windows Settings, and then click Scripts (Startup/Shutdown).

12.   Double-click Startup, and then click Add.

13.   In the Script Name box, type the universal naming convention (UNC) path of the BanglaTZUpdate.cmd file location within the Netlogon share as decided in Step 1.
For example, type \\contoso.com\NETLOGON\BanglaTZUpdate.cmd

14.   Click OK two times.

Once this is completed and AD replication has completed, all client computers that are within the DST Bangladesh OU will run the DST update startup script the next time that they restart, and any that are located within this time zone will observe the new DST settings.

Hotfix Available for Bangladesh 2009/2010 Daylight Saving Time

12/28/2009 Update: As announced today, Bangladesh has decided to end DST on December 31, 2009.  This hotfix does not address this most recent change on Bangladesh's time.  Please stay tuned for more information on Bangladesh's newest DST change.

According to an announcement from the Bangladesh government, the Bangladesh cabinet decided to advance Bangladesh Standard Time by one hour from 23:00:00 June 19th, 2009 to save electricity during evening peak hours. No DST end date has been announced at the time of this release. There was no DST for Bangladesh prior to this announcement.

This hotfix adds a new (GMT +06:00) Dhaka time zone with the following DST settings:

-          DST starts at 23:00:00 on June 19th, 2009 and will continue until end of 2009

-          Bias will change to UTC+7 in 2010 with no DST

Note:

When the Bangladesh government announces the final DST policy, a further update will be required.

Microsoft has produced a hotfix to implement this change.  If interested in downloading this hotfix, please refer KB978125

Hotfix Available for Fiji 2009/2010 Daylight Saving Time

Microsoft Windows Daylight Saving Time and Time Zone update now available (December 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/976098

Advisory: Mauritius Discontinues Daylight Saving Time in 2009

There will be no daylight saving time (DST) in Mauritius in 2009 despite positive reports from a recent DST trial, which began in October 2008 and ended in March 2009. Mauritius’ government announced that it would not repeat last year’s DST trial.  Microsoft Windows provides a way to prevent machines from switching into DST by un-checking the “Automatically adjust the clock for Daylight Saving Time” box in the Date and Time window.

Alternatively, customers in Mauritius can switch their computers to the  “Arabian Standard Time” time zone with a display name of “(GMT+04:00) Abu Dhabi, Muscat” or  the  “Georgian Standard Time” time zone with a display name of “(GMT+04:00) Tbilisi”.  These time zones have a bias of  UTC +4 which is the same as Mauritius 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 notes 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.

Microsoft Announces Update to Support Policy for Daylight-Saving Time or Time Zone Changes

As part of Microsoft’s continued focus on customer satisfaction, we are announcing a revision to the Microsoft Support Lifecycle policy regarding the availability of Daylight Saving Time (DST) or Time Zone (TZ) updates during the Extended Support phase.

DST or TZ updates are important because unless they are applied, the time zone setting for a computer’s clock and calendar, as well as the recorded and reported timestamps may be incorrect.  This change to the Microsoft Support Lifecycle policy will enable all Microsoft customers to obtain these broadly distributed DST or TZ updates and help ensure their computer’s time information is accurate.

There are currently two kinds of updates for DST or TZ:

1. The general distribution DST or TZ releases that are intended for broad consumption and made available via Microsoft and/or Windows Update two times every calendar year
2. Out-of-cycle DST or TZ hotfixes

Previously, both types of DST or TZ updates were made available at no charge only for products in the Mainstream Support phase. However, to obtain any of these updates for products in the Extended Support phase, customers had to purchase and enroll in the DST Extended Hotfix Support program.

As per the revised DST policy, Microsoft has decided to make the following changes for products that entered the Extended Support phase after January 1, 2009:

• General distribution of DST or TZ releases for products in the Extended Support phase will now be available at no-charge and be made available via Microsoft Update and/or Windows Update.  These general distribution updates will be provided twice a year on the northern hemisphere’s fall and winter.

• Customers who require DST or TZ updates outside of the general distribution of DST or TZ releases will need to enroll in an Extended Hotfix Support program to obtain a DST or TZ hotfix and pay any applicable hotfix fees.

The Microsoft Support Lifecycle (MSL) policy provides transparent, predictable information regarding the support lifecycle of Microsoft products. More information is available on the MSL Web site: http://support.microsoft.com/lifecycle.

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

Announcement: Microsoft Windows 2009 Daylight Saving Time and Time Zones Hotfix available for Egypt, Western Australia

Once again, as has happened in the past, a couple of countries will see new changes to their observation of Daylight Saving Time (DST) , this time in Egypt and Western Australia.

A new Microsoft Knowledge Base article is up – KB 974176 – noting the hotfix now 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.

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 in 2009.

To get the hotfix, click here to view and request hotfix downloads.

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

Microsoft strongly recommends that DST and time zone updates be installed on all impacted systems, devices and applications to ensure consistency with current DST rules and time zone settings worldwide. Customers should review the product updates available and posted on this site and at http://support.microsoft.com/gp/dst_prodlist for the latest and updated information of Microsoft products affected by daylight saving time.

An important note for Consumers

For those customers (consumers, small businesses) wondering "Does this mean I have to install the updates manually?" 

No.  Generally, consumers can wait for the updates to be installed via Windows Update rather than download and install these from the DLC.  And for end users who have their PCs managed by a central administrator, your IT folks will handle the distribution and updating of your PCs over the network. 

Additional information

Please note that where we have heard that changes may be coming to a territory but have yet to receive an official confirmation from a government, we indicate that the changes are "not yet confirmed."

As a reminder on our cadence (outlined here), our product teams are have moved to a semi-annual product update cadence (with provisions for out-of-band releases as needed).  Following the Windows regular cadence for publishing newly legislated DST rules and time zone updates, our "Cumulative DST and Time Zone Updates" will be released in November/ December (to the Download Centre and via Windows Update respectively) for the coming calendar year; we also provide semi-annual updates (like this one) in the July/August timeframe as needed. 

For each, the window closes for additional updates a few months (generally four to six) prior to the release date. 

Most Windows applications (and some services) reference the underlying OS for DST and time zone information, but some do not. The product and service groups with offerings that have internal DST or TZ references have agreed to follow the regular schedule for cumulative Windows OS DST & TZ updates. The regular Windows release provide a regular schedule for other product groups to follow, as noted in the DST & TZ Product Update Cadence policy. We hope that this will provide a more predictable way for our customers to anticipate and plan for our cumulative updates

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 19^th 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 KB972423 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 Saving 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 also 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 15^th 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 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 XP-based, Windows Server 2003-based, Windows Vista-based and Windows Server 2008-based computers”.

Notice: 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 15^th at midnight.   This information is subject to change as it has not been officially confirmed  by a Pakistani government source. 

Microsoft has produced a hotfix to implement this change for Windows Vista and Windows Server 2008.  If 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”.

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.

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 notes 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.
• We suggest that entities considering the DST 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

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 notes 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.
• We suggest that entities considering the DST 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.