title: IncludeDirectory generate error Invalid file name for file monitoring
body: <h2>Code</h2>
  
  <pre><code>var styleBundle = new StyleBundle("~/Content/Common") { Orderer = new FileBundleOrderer(server.MapPath("/Content/bundle.txt")) }
        .IncludeDirectory("~/Content", "*.css", false);
  </code></pre>
  
  <h2>Error message:</h2>
  
  <blockquote>
    <p>Invalid file name for file monitoring: '{ProjectPath}\Content'. Common<br>
    reasons for failure include:<br>
    - The filename is not a valid Win32 file name.<br>
    - The filename is not an absolute path.<br>
    - The filename contains wildcard characters.<br>
    - The file specified is a directory.<br>
    - Access denied.</p>
  </blockquote>
  
  <p><strong>'{ProjectPath}\Content'</strong> Content directory exist in project directory!!</p>
  
  <h2>Package version:</h2>
  
  <blockquote>
    <p>Microsoft.AspNet.Web.Optimi... 1.1.0</p>
  </blockquote>