Invalid url in calling ActionResult from controller through $.ajax in asp.net mvc

Hi All
   I have problem that I can not access ActionResult from mvc and showing Invalid URL in $.ajax

ActionController(Controller Name is Home)
========================
  public  ActionResult Logout()         {             Session.Abandon();             Session.Clear();             FormsAuthentication.SignOut();             FormsAuthentication.RedirectToLoginPage();
          // return RedirectToAction("Index","Home")   (Not redirect when using ../Home/Logout)             return Json(new { val = " ...