title: robots.txt IISExpress dynamic file giving 404
body: <p>I'm using iisexpress with ASP.NET MVC 4 and I've mapped robots.txt to a custom action like so:</p>
  
  <pre><code>        routes.MapRoute("Robots.txt",
              "robots.txt",
              new { controller = "Home", action = "Robots" });
  </code></pre>
  
  <p>When I set my development server to use IISExpress, i receive the standard IIS 404 error page:</p>
  
  <pre><code>Detailed Error Information:
  Module     IIS Web Core
  Notification       MapRequestHandler
  Handler    StaticFile
  Error Code     0x80070002
  Requested URL      http://localhost:25315/robots.txt
  Physical Path      c:\dev\myapp\myapp\robots.txt
  Logon Method       Anonymous
  Logon User     Anonymous
  </code></pre>
  
  <p>When I use Visual Studio Development Server, this seems to work fine and routes correctly.</p>
  
  <p>Is there a particularly web.config or other setting that I need to make to get this to work?</p>