Diagnostics in WCF

for diagnostics - add the following to config

<system.diagnostics>

    <sources>

      <source propagateActivity="true" name="System.ServiceModel" switchValue="Error,ActivityTracing">

        <listeners>

          <add type="System.Diagnostics.DefaultTraceListener" name="Default"></add>

          <add initializeData="c:\logs\blah.svclog" type="System.Diagnostics.XmlWriterTraceListener" name="traceListener"></add>

        </listeners>

      </source>

    </sources>

  </system.diagnostics>

interestingly, if you add this twice the config still works.
 for bugs that stop the request from ever reaching the service, check the event log