Logout Browser back button issue in ASP.Net


<asp:LinkButton ID="lnklogout" CssClass="navlinks" runat="server" Text="Logout" OnClick="lnklogout_Click"></asp:LinkButton>&nbsp;&nbsp;

protected void lnklogout_Click(object sender, EventArgs e)
        {
            Session.Abandon();
            Session.Clear();
            Session.RemoveAll();
            Response.Cache.SetCacheability(HttpCacheability.NoCache);
            FormsAuthentication.SignOut();
            Response.Redirect("~/Logout.aspx");
        }


<%@ Page Language="C#" AutoEventWireup="true" CodeBehind="Logout.aspx.cs" Inherits="Provider_Login.Logout" %>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
    <title></title>
    <script type="text/javascript">
        window.history.forward(1);
    </script>
    <script type="text/javascript">
        function preventBack() { window.history.forward(); }
        setTimeout("preventBack()", 5);
        window.onunload = function () { null };
    </script>
</head>
<body>
    <form id="form1" runat="server">
    <asp:ScriptManager ID="ScriptManager" runat="server">
    </asp:ScriptManager>
    <div>
    Please Wait...
        <asp:Timer ID="Timer1" runat="server" Interval="1" OnTick="Timer1_Tick">
        </asp:Timer>
    </div>
    </form>
</body>
</html>


using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;

namespace Provider_Login
{
    public partial class Logout : System.Web.UI.Page
    {
        protected void Page_Load(object sender, EventArgs e)
        {
            if (!IsPostBack)
            {
                Response.Cache.SetCacheability(HttpCacheability.NoCache);
                Response.Cache.SetExpires(DateTime.Now.AddSeconds(-1));
                Response.Cache.SetNoStore();
                Response.AppendHeader("Pragma", "no-cache");
            }
        }

        protected void Timer1_Tick(object sender, EventArgs e)
        {
            Response.Redirect("~/Login.aspx");
        }
    }
}

You Can Download the Working Code From here.