title: Configuring log file fields in IIS Express
body: <p>I'm dealing with log files and calculating the traffic usage of each website. The default logging is missing my required fields (<code>cs-host</code>, <code>sc-bytes</code>, <code>cs-bytes</code>). While I'm able to change these configuration in <code>Logging</code> section of IIS which I can select the fields I want to include or exclude in my logging. I couldn't find any way to change these configuration for IIS Express. Is there anyway to define the fields I want to include in the log in IIS express?</p>
  
  <p>Either using a GUI like the <code>Logging</code> in IIS configuration, Command line code, or just editing a configuration file?</p>
  
  <p><a href="https://i.stack.imgur.com/Nv5ma.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/Nv5ma.png" alt="IIS Log file configuration"></a></p>
  
  <p>I found the IIS Express logFile configuration but in there, but couldn't find anything about adding the fields  there:</p>
  
  <p><code>%userprofile%\documents\iisexpress\config\applicationhost.config</code></p>
  
  <p>which has logFile configuration in <code>SiteDefaults</code>:</p>
  
  <pre><code>&lt;siteDefaults&gt;
      &lt;logFile logFormat="W3C" directory="%IIS_USER_HOME%\Logs"/&gt;
      &lt;traceFailedRequestsLogging directory="%IIS_USER_HOME%\TraceLogFiles" enabled="true" maxLogFileSizeKB="1024" /&gt;
  &lt;/siteDefaults&gt;
  </code></pre>