WebHost failed to process a request error of Silverlight App

Question

I have got 4.5 Silverlight & RiaServices app under IIS 8. It starts fine but is impossible to login. All possible MS Windows features are enabled.

Error of Silverlight app:

load operation failed for query 'login'

Fidller gives error 500

Error in MS Windows Events with source System.ServiceModel 4.0.0.0 :

WebHost failed to process a request. Sender Information: System.ServiceModel.ServiceHostingEnvironment+HostingManager/45653674 Exception: System.ServiceModel.ServiceActivationException: The service '/Polaris/Services/Polaris-RIAServicesLibraryMain-Web-PolarisAuthenticationDomainService.svc' cannot be activated due to an exception during compilation. The exception message is: Method not found: 'System.Collections.Generic.IEnumerable1<System.Type> System.ServiceModel.DomainServices.Server.DomainServiceDescription.get_ComplexTypes()'.. ---> System.MissingMethodException: Method not found: 'System.Collections.Generic.IEnumerable1 System.ServiceModel.DomainServices.Server.DomainServiceDescription.get_ComplexTypes()'. at System.ServiceModel.DomainServices.Hosting.ServiceUtility.RegisterSurrogates(ContractDescription contractDesc, DomainServiceDescription domainServiceDescription) at System.ServiceModel.DomainServices.Hosting.ServiceUtility.LoadContractDescription(ContractDescription contractDesc, DomainServiceDescription domainServiceDescription) at Microsoft.ServiceModel.DomainServices.Hosting.SoapXmlEndpointFactory.CreateContract(DomainServiceDescription description) at Microsoft.ServiceModel.DomainServices.Hosting.SoapXmlEndpointFactory.CreateEndpoints(DomainServiceDescription description, DomainServiceHost serviceHost) at System.ServiceModel.DomainServices.Hosting.DomainServiceHost.CreateDescription(IDictionary`2& implementedContracts) at System.ServiceModel.ServiceHostBase.InitializeDescription(UriSchemeKeyedCollection baseAddresses) at System.ServiceModel.ServiceHost.InitializeDescription(Type serviceType, UriSchemeKeyedCollection baseAddresses) at System.ServiceModel.DomainServices.Hosting.DomainServiceHost..ctor(Type domainServiceType, Uri[] baseAddresses) at System.ServiceModel.DomainServices.Hosting.DomainServiceHostFactory.CreateServiceHost(Type serviceType, Uri[] baseAddresses) at System.ServiceModel.Activation.ServiceHostFactory.CreateServiceHost(String constructorString, Uri[] baseAddresses) at System.ServiceModel.ServiceHostingEnvironment.HostingManager.CreateService(String normalizedVirtualPath, EventTraceActivity eventTraceActivity) at System.ServiceModel.ServiceHostingEnvironment.HostingManager.ActivateService(ServiceActivationInfo serviceActivationInfo, EventTraceActivity eventTraceActivity) at System.ServiceModel.ServiceHostingEnvironment.HostingManager.EnsureServiceAvailable(String normalizedVirtualPath, EventTraceActivity eventTraceActivity) --- End of inner exception stack trace --- at System.ServiceModel.ServiceHostingEnvironment.HostingManager.EnsureServiceAvailable(String normalizedVirtualPath, EventTraceActivity eventTraceActivity) at System.ServiceModel.ServiceHostingEnvironment.EnsureServiceAvailableFast(String relativeVirtualPath, EventTraceActivity eventTraceActivity) Process Name: w3wp Process ID: 3512

Answer 1

I found that MS Windows 2012 has installed old version of RIA Services so I just installed a RIA Services SP2 and it works now!