title: Visual Studio Can't Create Virtual Directory
body: <p>On my Windows 7 x64 machine, I'm trying to launch debugging on an ASP.NET web site, hosted on a local IIS, from Visual Studio 2010 SP1.  My first step was to configure to use IIS, and to use the "Create Virtual Directory" option VS offers.  When I do so, I get this error:</p>
  
  <blockquote>
    <blockquote>
      <p>Configuring Web <code>http://localhost/MySite</code> for ASP.NET 4.0 failed.  You must manually configure this site for ASP.NET 4.0 in order for the site to run correctly.  Configuring the virtual directory for ASP.NET 4.0 failed. You may need to manually configure this site for ASP.NET 4.0 in order for your site to run correctly.</p>
    </blockquote>
  </blockquote>
  
  <p>This problem is similar to the one <a href="https://stackoverflow.com/questions/5273044/visual-studio-cant-create-web-site-in-iis">described here</a>, but in my case the default application pool is indeed set.  Any ideas?</p>
  
  <p>After the error message is given, another dialogue pops up saying that the virtual directory was created successfully (!!!!).  Indeed, when I open IIS Manager I can see the new application.  However, it doesn't work; I cannot launch the web application.</p>
  
  <p>I have another machine that has the same application configured the same way, and yet it works fine.  Bizarre.</p>