This is for fix the facebook authentication errors that comes with erros in ASP.NET default template

AccountController.ExternalLoginConfirmation.cs

[HttpPost]
[AllowAnonymous]
[ValidateAntiForgeryToken]
public async Task<ActionResult> ExternalLoginConfirmation(ExternalLoginConfirmationViewModel model, string returnUrl)
{
  if (User.Identity.IsAuthenticated)
  {
      return RedirectToAction("Manage");
  }

  if (ModelState.IsValid)
  {
      // Get the information about the user from the external login provider
      var result = await AuthenticationManager.AuthenticateAsync(DefaultAuthenticationTypes.ExternalCookie);

      // Here will check if user login done
      if (result == null || result.Identity == null) 
      {
          return RedirectToAction("Login");
      }

      var idClaim = result.Identity.FindFirst(ClaimTypes.NameIdentifier);
      if (idClaim == null)
      {
          return RedirectToAction("Login");
      }

      // Here getting login info
      var login = new UserLoginInfo(idClaim.Issuer, idClaim.Value); 
      var user = new ApplicationUser() { UserName = model.UserName };
      var resultUser = await UserManager.CreateAsync(user);
      if (resultUser.Succeeded)
      {
          resultUser = await UserManager.AddLoginAsync(user.Id, login);
          if (resultUser.Succeeded)
          {
              await SignInAsync(user, isPersistent: false);
              return RedirectToLocal(returnUrl);
          }
      }
      AddErrors(resultUser);
  }

  ViewBag.ReturnUrl = returnUrl;
  return View(model);
}