title: Using configSource, and changing restartOnExternalChanges for core section
body: <p>I'd like to use the <a href="http://msdn.microsoft.com/en-us/library/system.configuration.sectioninformation.configsource.aspx" rel="noreferrer">configSource</a> attribute of my web config section to define external files for various settings.</p>
  
  <p>Particularly, the appSettings section. This means my config file has the following entry:</p>
  
  <pre><code>&lt;appSettings configSource="My.AppSettings.config" /&gt;
  </code></pre>
  
  <p>However, if this file is updated, the settings are not automatically picked up, which would have been the case if the settings were manually included in the web.config</p>
  
  <p>Further investigation lead me to the <a href="http://msdn.microsoft.com/en-us/library/system.configuration.sectioninformation.restartonexternalchanges.aspx" rel="noreferrer">restartOnExternalChanges</a> attribute. This can apparently be used with <code>&lt;section/&gt;</code> elements to define whether externals files identified by configSource can trigger restarts or not. Great! or so I thought.</p>
  
  <p>However, when trying to define the appSettings section, and changing the restartOnExternalChanges value, I see the same error encountered <a href="http://www.webdeveloper.com/forum/showthread.php?t=111685" rel="noreferrer">here</a>, because the appSettings section is defined in the machine.config - a file I cannot change.</p>
  
  <p>Does anyone know if its possible to get these two settings to work together, for sections already defined at a higher-level?</p>