<system.diagnostics>
        <sources>
            <source name="System.ServiceModel.MessageLogging" switchValue="Warning,ActivityTracing">
                <listeners>
                    <add type="System.Diagnostics.DefaultTraceListener" name="Default">
                        <filter type="" />
                    </add>
                    <add name="ServiceModelMessageLoggingListener">
                        <filter type="" />
                    </add>
                </listeners>
            </source>
        </sources>
        <sharedListeners>
            <add
                initializeData="app_messages.svclog"
                type="System.Diagnostics.XmlWriterTraceListener, System, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089"
                name="ServiceModelMessageLoggingListener" traceOutputOptions="Timestamp">
                <filter type="" />
            </add>
        </sharedListeners>
    </system.diagnostics>