Question

We have working ASP.Net web application with WCF. wcf service hosted as a windows service. All is fine. Then we made a change so that service contract will have different namespace (From Namespace1.IserviceContract to Namespace2.IserviceContract). After the change we deployed to the server and getting following error when we try to instantiate the service object.

    System.InvalidOperationException: An endpoint configuration section for contract 'Namespace2.IserviceContract' could not be loaded because more than one endpoint configuration for that contract was found. Please indicate the preferred endpoint configuration section by name.

Generated: Fri, 06 Jul 2012 21:02:56 GMT


System.Web.HttpUnhandledException: Exception of type 'System.Web.HttpUnhandledException' was thrown. ---> System.InvalidOperationException: An endpoint configuration section for contract 'Namespace2.IserviceContract' could not be loaded because more than one endpoint configuration for that contract was found. Please indicate the preferred endpoint configuration section by name.
   at System.ServiceModel.Description.ConfigLoader.LookupChannel(String configurationName, String contractName, Boolean wildcard)
   at System.ServiceModel.Description.ConfigLoader.LoadChannelBehaviors(ServiceEndpoint serviceEndpoint, String configurationName)
   at System.ServiceModel.ChannelFactory.ApplyConfiguration(String configurationName, Configuration configuration)
   at System.ServiceModel.ChannelFactory.ApplyConfiguration(String configurationName)
   at System.ServiceModel.ChannelFactory.InitializeEndpoint(String configurationName, EndpointAddress address)
   at System.ServiceModel.ChannelFactory`1..ctor(String endpointConfigurationName, EndpointAddress remoteAddress)
   at System.ServiceModel.EndpointTrait`1.CreateSimplexFactory()
   at System.ServiceModel.EndpointTrait`1.CreateChannelFactory()
   at System.ServiceModel.ClientBase`1.CreateChannelFactoryRef(EndpointTrait`1 endpointTrait)
   at System.ServiceModel.ClientBase`1.InitializeChannelFactoryRef()
   at System.ServiceModel.ClientBase`1..ctor()
   at TestApplication.ManagementWrapper.VerifyAuthentication(Int32 appId, String Token)
   at TestApplication.VerifyAuthentication(String tokenstring)

we did a research about this issue and found that this type if exception shows up if we have two client endpoints defined in our web.config file. however we are certain that we have only one client endpoint defined. More over this exception shows up only in the server. local works fine. here is our service model:

<system.serviceModel>
    <bindings>
      <netTcpBinding>
        <binding name="NetTcpBinding_Management" closeTimeout="00:01:00" openTimeout="00:01:00" receiveTimeout="00:10:00" sendTimeout="00:01:00" transactionFlow="false" transferMode="Buffered" transactionProtocol="OleTransactions" hostNameComparisonMode="StrongWildcard" listenBacklog="10" maxBufferPoolSize="4194304" maxBufferSize="2147483647" maxConnections="10" maxReceivedMessageSize="2147483647">
          <readerQuotas maxDepth="32" maxStringContentLength="2147483647" maxArrayLength="2147483647" maxBytesPerRead="32768" maxNameTableCharCount="2147483647" />
          <reliableSession ordered="true" inactivityTimeout="00:10:00" enabled="false" />
          <security mode="None" />
        </binding>
      </netTcpBinding>
    </bindings>
    <client>
      <endpoint address="net.tcp://servername:9010/Management/service/ManagementService" binding="netTcpBinding" bindingConfiguration="NetTcpBinding_Management" contract="Namespace2.IserviceContract" name="NetTcpBinding_IserviceContract" />
    </client>
  </system.serviceModel>

we also tried to restart IIS and application pool. Still getting the same exception.

Answer 1

Try searching your web.config for another that is using the web address as your ManagementService. Also, search the web.config for any reference to the old namespace (contract=”Namespace1.IserviceContract”). Don’t forget to check for extra .config files. That little gotcha has burned me before.