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Silverlight 5 WCF RIA Application References

Saturday, April 13, 2013

When developing Silverlight 5 applications with WCF RIA, you might encounter the following error at runtime: "Could not load file or assembly 'System.ServiceModel.Web.Extensions, Version=, Culture=neutral, PublicKeyToken=31bf3856ad364e35' or one of its dependencies. The system cannot find the file specified."

The error dialog is a bit misleading as it is asking for version of System.ServiceModel.Web.Extensions when the correct version is

To avoid this error make sure that these 4 references in the Silverlight 5 application are included and configured correctly:

Reference Runtime Version Specific Version Copy Local Version Path
System.ServiceModel v4.0.30319 False False C:\Program Files (x86)\Reference Assemblies\Microsoft\Framework\Silverlight\v5.0\System.ServiceModel.dll
System.ServiceModel.DomainServices.Client v2.0.50727 True True C:\Program Files (x86)\Microsoft SDKs\RIA Services\v1.0\Libraries\Silverlight\System.ServiceModel.DomainServices.Client.dll
System.ServiceModel.DomainServices.Client.Web v2.0.50727 True True C:\Program Files (x86)\Microsoft SDKs\RIA Services\v1.0\Libraries\Silverlight\System.ServiceModel.DomainServices.Client.Web.dll 
System.ServiceModel.Web.Extensions v4.0.30319 True True C:\Program Files (x86)\Microsoft SDKs\Silverlight\v5.0\Libraries\Client\System.ServiceModel.Web.Extensions.dll


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