title: Multiple Application_Start events firing
body: <p>I am debugging an ASP.NET 2.0 application that is suffering from slow loading of the initial page.</p>
  
  <p>Through adding logging, I've found that the <code>Application_Start</code> event fires twice on startup with a short delay between the two events. The <code>Session_Start</code> event also fires twice, with the same Session ID value.</p>
  
  <p>e.g.</p>
  
  <pre>
  [Header]
  2010-09-10 14:52:36.331 INFO  Web.Global.Application_Start          START
  2010-09-10 14:52:37.409 INFO  Web.Global.Session_Start              Session.SessionID=xxqjvun2ce2yqsumq1hfoj45
  [Header]
  2010-09-10 14:53:10.028 INFO  Web.Global.Application_Start          START
  2010-09-10 14:53:10.325 INFO  Web.Global.Session_Start              Session.SessionID=xxqjvun2ce2yqsumq1hfoj45
  </pre>
  
  <p>I am running this on my local machine, under IIS 5.1. The project also uses ASP.NET MVC and the aspx page URL being used is altered using routing, <a href="http://haacked.com/archive/2008/03/11/using-routing-with-webforms.aspx" rel="noreferrer">using the technique shown on Phil Haack's site</a>.</p>
  
  <p>Any suggestions about what could cause this?</p>