WCF turn on IncludeExceptionDetailInFaults

Error: The server was unable to process the request due to an internal error.
For more information about the error, either turn on IncludeExceptionDetailInFaults (either from ServiceBehaviorAttribute or from the configuration behavior) on the server in order to send the exception information back to the client, or turn on tracing as per the Microsoft .NET Framework 3.0 SDK documentation and inspect the server trace logs.System.Exception {System.ServiceModel.FaultException}

Reason/Solution:
When any kind of error occur calling a WCF endpoint from client, client will receive a generic message ( as given above ) for security reason.

If you want to see the full details of the error, you need to change the app.config file for the WCF Host to include full exception details while sending it to clients.

Host App.Config:

<configuration>
<system.serviceModel>
  <services>
    <!-- Step 1. Add a behaviorConfiguration attribute -->
    <service
      name="Microsoft.WCF.Documentation.SampleService"
      behaviorConfiguration="metadataAndDebug">
      <host>
        <baseAddresses>
          <add baseAddress="http://localhost:8080/SampleService" />
        </baseAddresses>
      </host>
      <endpoint
         address="mex"
         binding="mexHttpBinding"
         contract="IMetadataExchange"
      />
    </service>
  </services>
  <behaviors>
    <serviceBehaviors>
      <!-- Step 2. Add a new behavior below.-->
      <behavior name="metadataAndDebug">
        <serviceMetadata  httpGetEnabled="true" httpGetUrl=""/>
      <!-- Step 3. Add a <serviceDebug> element -->
    <serviceDebug httpHelpPageEnabled="true" includeExceptionDetailInFaults="true" />
      </behavior>
    </serviceBehaviors>
  </behaviors>
</system.serviceModel>
</configuration>

Article:MSDN


This setting is only recommended for DEV purpose.