title: Umbraco / TeamCity BuildAgent nullReference error showing in Event Viewer
body: <p>I'm noticing a strange error cropping up regularly with a site I've inherited the maintenance of from a former colleague.</p>
  
  <p>Does it ring any bells for any of you out there?</p>
  
  <p>It's an umbraco v 4.0.4.2 site, and TeamCity is most definitely NOT installed on this machine.</p>
  
  <p>Here's the message:</p>
  
  <p>Exception information: 
      Exception type: NullReferenceException 
      Exception message: Object reference not set to an instance of an object. </p>
  
  <p>Request information: 
      Request URL: http://www.[[some website name]].co.uk/default.aspx 
      Request path: /default.aspx 
      User host address: [[some ip address]]
      User:
      Is authenticated: False 
      Authentication Type:<br>
      Thread account name: NT AUTHORITY\NETWORK SERVICE </p>
  
  <p>Thread information: 
      Thread ID: 1 </p>
  
  <pre><code>Thread account name: NT AUTHORITY\NETWORK SERVICE 
  
  Is impersonating: False 
  
  Stack trace:    
  </code></pre>
  
  <p>at umbraco.requestHandler..ctor(XmlDocument _umbracoContent, String url) in d:\TeamCity\buildAgent\work\7380c184e9fcd3ea\umbraco\presentation\requestHandler.cs:line 230</p>
  
  <p>at umbraco.UmbracoDefault.Page_PreInit(Object sender, EventArgs e) in d:\TeamCity\buildAgent\work\7380c184e9fcd3ea\umbraco\presentation\default.aspx.cs:line 113</p>
  
  <p>at System.Web.Util.CalliHelper.EventArgFunctionCaller(IntPtr fp, Object o, Object t, EventArgs e)</p>
  
  <p>at System.Web.Util.CalliEventHandlerDelegateProxy.Callback(Object sender, EventArgs e)</p>
  
  <p>at System.EventHandler.Invoke(Object sender, EventArgs e)</p>
  
  <p>at System.Web.UI.Page.OnPreInit(EventArgs e)</p>
  
  <p>at System.Web.UI.Page.PerformPreInit()</p>
  
  <p>at System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint)</p>
  
  <p>Custom event details: </p>
  
  <p>For more information, see Help and Support Center at </p>