FIX: You may experience issues with Windows Communication Foundation peer channel connections

A hotfix is now available for the Microsoft Windows Communication Foundation (WCF). This hotfix corrects several issues with WCF peer channel connections.

This hotfix fixes the following issues that were not previously documented in a Microsoft Knowledge Base article:

• You may receive a System.NullReferenceException exception if the following conditions are true:
  • A client computer that uses IPv4 tries to connect to a destination computer.
  • The destination computer has a host name that resolves to an IPv6 address.
  • On the client computer, IPv6 is either not supported or disabled.
  • The URI that is provided when the channel is created already includes an IPv6 address.
  This exception may be thrown from one of the following methods:
  • The IChannel.EndOpen method
  • The End method of the first asynchronous operation that is invoked on the channel
  Note The exception may be thrown from other methods if those methods try to open the underlying transport channel asynchronously.
• When a new peer tries to join the mesh, the peer may not communicate with existing peer members. Additionally, the mesh may become partitioned. This behavior may occur in a peer channel application that has a default custom resolver. This behavior occurs when the client cannot communicate with the configured resolver service because of network issues.
• CPU utilization on the client computer may reach 100 percent when you run a peer channel application for a long time. This behavior may last for several minutes or until you close the application.

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 Microsoft .NET Framework 3.0 service pack 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: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.

Prerequisites

You must have the .NET Framework 3.0 installed to apply this hotfix.

Restart information

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

Hotfix 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.

The Microsoft .NET Framework 3.0, x86-based versions

The Microsoft .NET Framework 3.0, x64-based versions

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: For more information about Windows Communication Foundation in the .NET Framework, visit the following Microsoft Developer Network (MSDN) Web site: