Description of updates to APIs that enable Windows-based applications to retrieve historically accurate time stamps

This article describes updates to APIs that enable Windows-based applications to retrieve historically accurate time stamps.

What time functions are updated?

The following time functions are updated by this update:

• SystemTimeToTzSpecificLocalTime() Converts a time in Coordinated Universal Time (UTC) to a specified time zone's corresponding local time.
• TzSpecificTimeToSystemTime() Converts a local time to a time in Coordinated Universal Time (UTC).

Note The functions that are listed here use a TIME_ZONE_INFORMATION structure that specifies the START DATE and the END DATE for daylight saving time (DST). By default, the current DST rules are used when no such structure is provided.

When to use these functions in an application

Most date and time stamps that are created and displayed in Windows and in many applications are stored as UTC. Then, they are rendered in local time by using system APIs. Examples of these include Windows file time stamps, Outlook sent and received dates, and event logging time stamps.

Not all built-in, Windows-based applications use these newly updated APIs. However, they are available to all applications, including third-party applications. These functions are useful in many scenarios, such as a user auditing scenario in which the ability to use DST rules for previous years on a current Windows service pack is important.

Generally, if an application requires historically accurate time stamps, these functions should be used.

How to use these functions in an application

For information about syntax, parameters, return value, and examples on how to use these functions in an application, please visit the following Microsoft Developer Network (MSDN) Web sites:

SystemTimeToTzSpecificLocalTime FunctionTzSpecificLocalTimeToSystemTime FunctionNote This article supersedes article 944340, which describes an earlier version of these APIs. This update improves the performance of the functions, and enables historically accurate time-stamp lookup functionality that was introduced in 944340.

This update applies to the following Windows operating systems:

• Windows XP Service Pack 3 (SP3)
• Windows Server 2003 Service Pack 2 (SP2)
• Windows Vista Service Pack 1 (SP1)
• Windows Server 2008

Hotfix information for Windows XP

A supported hotfix is available from Microsoft. However, this hotfix is intended to correct only the problem that is described in this article. Apply this hotfix only to systems that are experiencing this specific problem.

If the hotfix is available for download, there is a "Hotfix download available" section at the top of this Knowledge Base article. If this section does not appear, submit a request to Microsoft Customer Service and Support to obtain the hotfix.

Note If additional issues occur or if any troubleshooting is required, you might have to create a separate service request. The usual support costs will apply to additional support questions and issues that do not qualify for this specific hotfix. For a complete list of Microsoft Customer Service and Support telephone numbers or to create a separate service request, visit the following Microsoft Web site: Note The "Hotfix download available" form displays the languages for which the hotfix is available. If you do not see your language, it is because a hotfix is not available for that language.

Important Windows Vista and Windows Server 2008 hotfixes are included in the same packages. However, only one of these products may be listed on the �Hotfix Request� page. To request the hotfix package that applies to both Windows Vista and Windows Server 2008, just select the product that is listed on the page.

Prerequisites

To apply this hotfix, you must have Windows XP SP3 installed.

For more information, click the following article number to view the article in the Microsoft Knowledge Base:

Restart requirement

You have to restart the computer after you apply this hotfix.

Hotfix replacement information

This hotfix replaces the following hotfix:

For more information, click the following article number to view the article in the Microsoft Knowledge Base:

File information

The English version of this hotfix 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.

Windows XP with Service Pack 3, x86-based versions

Hotfix information for Windows Server 2003

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

If the hotfix is available for download, there is a "Hotfix download available" section at the top of this Knowledge Base article. If this section does not appear, contact Microsoft Customer Service and Support to obtain the hotfix.

Note If additional issues occur or if any troubleshooting is required, you might have to create a separate service request. The usual support costs will apply to additional support questions and issues that do not qualify for this specific hotfix. For a complete list of Microsoft Customer Service and Support telephone numbers or to create a separate service request, visit the following Microsoft Web site: Note The "Hotfix download available" form displays the languages for which the hotfix is available. If you do not see your language, it is because a hotfix is not available for that language.

Prerequisites

To apply this hotfix, you must have the following installed:

• Windows Server 2003 SP2
  
  For more information, click the following article number to view the article in the Microsoft Knowledge Base:
  889100� How to obtain the latest service pack for Windows Server 2003
• The 944340 hotfix
  
  For more information, click the following article number to view the article in the Microsoft Knowledge Base:
  944340� The time stamps are incorrect after you apply update 928388 and then change the time settings to a year that is earlier than 2007 in Windows XP and in Windows Server 2003

Restart requirement

You have to restart the computer after you apply this hotfix.

Hotfix replacement information

This hotfix replaces the following hotfix:

For more information, click the following article number to view the article in the Microsoft Knowledge Base:

File information

The English version of this hotfix 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.

Windows Server 2003 with Service Pack 2, x86-based versions

Windows Server 2003 with Service Pack 2, Itanium-based versions

Windows Server 2003 with Service Pack 2, x64-based versions

Hotfix information for Windows Vista and for Windows Server 2008

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

If the hotfix is available for download, there is a "Hotfix download available" section at the top of this Knowledge Base article. If this section does not appear, contact Microsoft Customer Service and Support to obtain the hotfix.

Note If additional issues occur or if any troubleshooting is required, you might have to create a separate service request. The usual support costs will apply to additional support questions and issues that do not qualify for this specific hotfix. For a complete list of Microsoft Customer Service and Support telephone numbers or to create a separate service request, visit the following Microsoft Web site: Note The "Hotfix download available" form displays the languages for which the hotfix is available. If you do not see your language, it is because a hotfix is not available for that language.

Prerequisites

To apply this hotfix on Windows Vista-based computer, you must have Windows Vista SP1 installed.

For more information, click the following article number to view the article in the Microsoft Knowledge Base: No prerequisites are required for Windows Server 2008-based computers.

Restart requirement

You have to restart the computer after you apply this hotfix.

Hotfix replacement information

This hotfix does not replace a previously released hotfix.

File information

The English version of this hotfix 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.

Windows Vista and Windows Server 2008 file information notes

The .manifest files and the .mum files that are installed in each environment are listed separately in the "Additional file information for Windows Server 2008 and for Windows Vista" section. These files and their associated .cat (security catalog) files are critical to maintaining the state of the updated component. The .cat files are signed with a Microsoft digital signature. The attributes of these security files are not listed.

For all supported x86-based versions of Windows Server 2008 and of Windows Vista

For all supported x64-based versions of Windows Server 2008 and of Windows Vista

For all supported IA-64-based versions of Windows Server 2008

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

Additional file information for Windows Server 2008 and Windows Vista

Additional files for all supported x86-based versions of Windows Server 2008 and of Windows Vista

Additional files for all supported x64-based versions of Windows Server 2008 and of Windows Vista

Additional files for all supported IA-64-based versions of Windows Server 2008