title: why after validation is false HttpContext.Current.Request.IsAuthenticated
body: <p>I've created a login on my website using forms authentication, 
  I do not understand why after creating the ticket and adding it to the cookies</p>
  
  <p>if I check for <code>HttpContext.Current.Request.IsAuthenticated</code></p>
  
  <p>i get false. Only on the successive request the user become authenticated</p>
  
  <p>this is my code</p>
  
  <pre><code>var fat = new FormsAuthenticationTicket(
      1,
      username,
      DateTime.Now,
      DateTime.Now.AddMinutes(20),
      rememberMe,
      contact.Id + "," + contact.Role.Id,
      FormsAuthentication.FormsCookiePath);
  HttpContext.Current.Response.Cookies.Add(new HttpCookie(FormsAuthentication.FormsCookieName, FormsAuthentication.Encrypt(fat)));
  </code></pre>
  
  <p>at this point if I check for HttpContext.Current.Request.IsAuthenticated i get false, i thought a this point the user is authenticated...</p>
  
  <p>this is my config </p>
  
  <pre><code>&lt;authentication mode="Forms"&gt;
      &lt;forms loginUrl="/Admin/Login.aspx" name="FormAuthentication" /&gt;
  &lt;/authentication&gt;
  &lt;authorization&gt;
      &lt;deny users="?"/&gt;
  &lt;/authorization&gt;
  </code></pre>
  
  <p>thanks.              </p>