You may lose some events when you subscribe to some events that are in multiple event logs on a computer that is running Windows Server 2008 or Windows Vista

An application or service subscribes to some events that are in multiple event logs by using Windows Management Instrumentation (WMI) or Windows APIs on a computer that is running Windows Server 2008 or Windows Vista.

In this scenario, the application or service may miss some expected events. This issue causes function failure in the application or service.

For example, an application subscribes to an event to monitor the user accounts that are created. Because of this issue, some newly created user accounts are not detected by this application.

This issue occurs because the Windows Event Log service misses some events when the service sends the notifications.

The Windows Event Log service maintains a unique view for all event logs. By using the unique view, the service retrieves newly added records from different event log channels and then sends notification to subscribers. Some examples of some event log channels are the security, application, and system event logs.

If no more records are found, the Windows Event Log service enters into an EOF state. When a new record arrives, the state is reset and the service continues to read new record.

When the state is reset, the Windows Event Log service does not scan all event log channels to detect all new records. The service only scans the current event log channel. This behavior causes the service to miss the new records in the other event log channels.

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, the computer must be running one of the following operating systems:

• Windows Vista Service Pack 1 (SP1)
• Windows Vista Service Pack 2 (SP2)
• Windows Server 2008
• Windows Server 2008 Service Pack 2 (SP2)

Restart requirement

You must restart the computer after you apply this hotfix.

Hotfix replacement information

This hotfix does not replace any other 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.

For all supported x86-based versions of Windows Server 2008 and of Windows Vista SP1

For all supported x86-based versions of Windows Server 2008 SP2 and of Windows Vista SP2

For all supported Itanium-based versions of Windows Server 2008

For all supported Itanium-based versions of Windows Server 2008 SP2

For all supported x64-based versions of Windows Server 2008 and of Windows Vista SP1

For all supported x64-based versions of Windows Server 2008 SP2 and of Windows Vista SP2

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

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

Additional file information for Windows Server 2008 and for Windows Vista

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

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

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

For more information about how to subscribe to events in an event log, visit the following Microsoft Web site: For more information about "Receiving a WMI Event," visit the following Microsoft Web site: For more information about how to receive an event, visit the following Microsoft Web site:For more information about the EvtNext Function, visit the following Microsoft Web site: