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Provide the SYMPTOMS/SUMMARY of the issue:

The government of Turkey has decided to change the 2011 DST schedule. It now starts Monday March 28th instead of Sunday March 27th. 

This hotfix contains two changes

1.It adds a new Windows (UTC +2:00) timezone, Turkey Standard Time. The display name is "(UTC +2:00) Istanbul "

2.It removes the term "Istanbul" from the display name of the existing timezone. The revised displayname is "(UTC +2:00) Athens, Bucharest"

Describe the steps to RESOLVE/WORK AROUND the symptoms:

To update Windows DST support

1. Install the hotfix

2. Choose the new timezone, Turkish Standard Time, which has displayname (UTC +2:00) Istanbul

Registry Key Information

[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Time Zones\Turkey Standard Time]



[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Time Zones\Turkey Standard Time\Dynamic DST]









This software update is scheduled to ship in the following service pack(s) : It is available as a hotfix only.

Prerequisites to install the software update (be specific for multiple product(s))
To install this hotfix you must be running one of the following operating system versions :

*Windows XP Service Pack 3 

*Windows Vista Service Pack 1 
Windows Vista Service Pack 2 

*Windows Server 2003 Service Pack 2 

*Windows Server 2008 
Windows Server 2008 Service Pack 2 

*Windows Server 2008 R2
*Windows Server 2008 R2 Service Pack 1 

* Windows 7
* Windows 7 Service Pack 1

Restart requirements : You may need to reboot after installing this hotfix.

This software update replaces the following software update:
This hotfix supplements the December 2010 Windows Daylight Saving Time Cumulative Update , KB 2443685

Should this article link to other KB articles? If yes, list them.
This hotfix supplements the December 2010 Windows Daylight Saving Time Cumulative Update, KB 2443685


A supported hotfix is now available from Microsoft. However, it is intended to correct only the problem that is described in this article. Apply it only to systems that are experiencing this specific problem. This hotfix may receive additional testing. Therefore, if you are not severely affected by this problem, we recommend that you wait for the next P1 that contains this hotfix.

To resolve this problem immediately, contact Microsoft Customer Support Services to obtain the hotfix. For a complete list of Microsoft Customer Support Services telephone numbers and information about support costs, visit the following Microsoft Web site: In special cases, charges that are ordinarily incurred for support calls may be canceled if a Microsoft Support Professional determines that a specific update will resolve your problem. The usual support costs will apply to additional support questions and issues that do not qualify for the specific update in question.The P1 version of this P2 has the file attributes (or later file attributes) that are listed in the following table. The dates and times for these files are listed in Coordinated Universal Time (UTC). When you view the file information, it is converted to local time. To find the difference between UTC and local time, use the Time Zone tab in the Date and Time item in Control Panel.


Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.

More Information

For more informationP1, click the following article numberP2 to view the articleP2 in the Microsoft Knowledge Base:

P3 P4

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