This article has been archived. It is offered "as is" and will no longer be updated.
When you run a Microsoft Windows Communication Foundation (WCF) application, you may experience slow performance. This problem occurs if the following conditions are true:
In the Windows Communication Foundation application, you use many types.
You apply the KnownTypeAttribute class to these types.
These types are derived from the same base type.
The serialization code that imports these types recursively generates the list of the types to which the DataContractAttribute class is applied. This process consumes lots of resources.
A supported hotfix is now available from Microsoft. However, it is intended to correct only the problem that this article describes. Apply it only to systems that are experiencing this specific problem.
To resolve this problem, 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.
You must have the Microsoft .NET Framework 3.0 installed to apply this hotfix.
You do not have to restart the computer after you apply this hotfix.
Hotfix replacement information
This hotfix does not replace any other hotfixes.
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 .NET Framework 3.0, x86-based versions
The .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 about Windows Communication Foundation, visit the following Microsoft Developer Network (MSDN) Web site: