FIX: You experience unexpectedly high CPU usage when you run a .NET Framework 2.0-based application that uses the LdapConnection.BeginSendRequest method

This article has been archived. It is offered "as is" and will no longer be updated.
When you run a Microsoft .NET Framework 2.0-based application that uses the LdapConnection.BeginSendRequest method, you experience unexpectedly high CPU usage.This problem occurs when you specify ReturnPartialResultsAndNotifyCallback for the partialMode argument of the LdapConnection.BeginSendRequest method.
This problem occurs because the LdapConnection.BeginSendRequest method adds an entry to the partialResultsProcessor list in the LdapConnection class. The partialResultsProcessor list continuously polls to check for changes in the Lightweight Directory Access Protocol (LDAP) query. Therefore, the PartialResultsRetriever class creates a dedicated thread that waits for notifications. This thread consumes significant CPU resources.

If nothing changes in the LDAP query, the LDAP response is interpreted as an LDAP time-out. Then, the ConstructResponse method throws an exception of the LdapException class. The ErrorCode property of the exception has a value of LDAP_TIMEOUT. This exception is handled at the next level and consumes more CPU resources.

Hotfix information

A supported hotfix is now available from Microsoft, but it is only intended to correct the problem that this article describes. Apply it only to systems that are experiencing this specific problem.

To resolve this problem, contact Microsoft Product Support Services to obtain the hotfix. For a complete list of Microsoft Product Support Services telephone numbers and information about support costs, visit the following Microsoft Web site:Note 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.


No prerequisites are required.

Restart requirement

You do not have to restart your computer after you apply this hotfix.

Software update replacement information

This hotfix does not replace any other hotfixes.

File information

The global 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.
Microsoft Windows Server 2003, x64-based editions
File nameFile versionFile sizeDateTimePlatform
Windows Server 2003, Enterprise Edition for Itanium-based Systems
File nameFile versionFile sizeDateTimePlatform
Windows Server 2003
File nameFile versionFile sizeDateTimePlatform
Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.
For more information about software update terminology, click the following article number to view the article in the Microsoft Knowledge Base:
824684 Description of the standard terminology that is used to describe Microsoft software updates

Article ID: 918995 - Last Review: 01/17/2015 14:39:35 - Revision: 2.0

Microsoft .NET Framework 2.0

  • kbnosurvey kbarchive kbbug kbfix kbqfe KB918995