ASP.NET MVC: return Redirect and ViewData

I have a login box in my MasterPage. Whenever the login information is not correct, I valorize `ViewData["loginError"]` to show the error message to the user. Login is an action of the UserController, so the form that contains the login has `action = "/User/Login"`. As a user can try to log in from any page, in case of success I redirect him to his personal page, but in case of error I want him to stay on the very same page where he tried to login. I've found that this works: ``` return Redirect(Request.UrlReferrer.ToString()); ``` but it seems that, as I'm not returning a proper view, the data on ViewData is lost, so I cannot show the error message. Any suggestion on how to solve this and similar problems? Thanks