title: Inscrutable error when switching from Cassini to IIS Express 8
body: <p>I've been working on a web project in MVC3 for several months. I've been using Visual Studio's built-in web server (Cassini) for development, but have found I need to use IIS Express to support HTTPS.</p>
  
  <p>After installing IIS Express 8, I right-clicked the project in VS and selected "Use IIS Express...", and allowed it to create a site for IIS. Now when I attempt to test my site, I get the following error:</p>
  
  <pre><code>Specified argument was out of the range of valid values.
  Parameter name: site
  
  Stack Trace:
  [ArgumentOutOfRangeException: Specified argument was out of the range of valid values.
  Parameter name: site]
     System.Web.HttpRuntime.HostingInit(HostingEnvironmentFlags hostingFlags, PolicyLevel policyLevel, Exception appDomainCreationException) +298
  
  [HttpException (0x80004005): Specified argument was out of the range of valid values.
  Parameter name: site]
     System.Web.HttpRuntime.FirstRequestInit(HttpContext context) +9850940
     System.Web.HttpRuntime.EnsureFirstRequestInit(HttpContext context) +101
     System.Web.HttpRuntime.ProcessRequestNotificationPrivate(IIS7WorkerRequest wr, HttpContext context) +254
  </code></pre>
  
  <p>The stack trace does not reference any of my code, and my code does not contain any variables named <code>site</code>. I have a property named <code>Site</code> in a few places, but no <code>site</code>.</p>
  
  <p>Furthermore, the exception doesn't even trip the debugger. Instead of breaking execution in VS, the error appears in the browser as a standard yellow ASP.NET error page (although I suppose this may be expected behavior when using IIS instead of Cassini).</p>
  
  <p>I'm not using any HTTPS code in my project yet, and the error occurs whether I've enabled HTTPS in the project properties or not. I should also mention that our production server runs IIS 7 proper, and I've never encountered this problem there.</p>
  
  <p>So, any idea what's going wrong? I can provide source code, but currently I have no idea where the error is even originating.</p>