private void Member_logOut()
{
HttpContext.Current.Session.Abandon();
//Session.Clear();
SiteCookie.RemoveAll();
FormsAuthentication.SignOut();
HttpCookie oldCookie = new HttpCookie(".ASPXAUTH");
oldCookie.Expires = DateTime.Now.AddDays(-1);
HttpContext.Current.Response.Cookies.Add(oldCookie);
//// clear authentication cookie
HttpCookie cookie1 = new HttpCookie(FormsAuthentication.FormsCookieName, "");
cookie1.Expires = DateTime.Now.AddDays(-1);
HttpContext.Current.Response.Cookies.Add(cookie1);
// clear session cookie (not necessary for your current problem but i would recommend you do it anyway)
HttpCookie cookie2 = new HttpCookie("ASP.NET_SessionId", "");
cookie2.Expires = DateTime.Now.AddDays(-1);
HttpContext.Current.Response.Cookies.Add(cookie2);
cookie2 = new HttpCookie("AdminRememberUserCookieTime", DateTime.MinValue.ToString());
cookie2.Expires = DateTime.Now.AddDays(-1);
HttpContext.Current.Response.Cookies.Add(cookie2);
HttpContext.Current.Response.Cache.SetCacheability(HttpCacheability.NoCache);
HttpContext.Current.Response.Cache.SetNoStore();
Response.Redirect("adminLogin.aspx", false);
}