title: Allow only anonymous users via web.config authorization
body: <p>I want to use authorization in the web.config to block access to SignUp.aspx to authenticated users.  It cannot be accessed by user such as their roles is administrator and Guest.</p>
  
  <pre><code>&lt;location path="SignUp.aspx"&gt;
      &lt;system.web&gt;
          &lt;authorization&gt;
              &lt;allow users="?"/&gt;
          &lt;/authorization&gt;
      &lt;/system.web&gt;
  &lt;/location&gt;
  
      &lt;authentication mode="Forms"&gt;
          &lt;forms name="AuthCookie" loginUrl="Login.aspx" timeout="60" 
                             defaultUrl="Index.aspx"/&gt;
      &lt;/authentication&gt;
      &lt;authorization&gt;
          &lt;deny users="?"/&gt;
      &lt;/authorization&gt;
  </code></pre>