In ASP.NET you can seamlessly rename cookies on the fly with the help the PreSendRequestHeaders and BeginRequest events of the HttpApplication class.

Both events call EventArgs delegates, with the sender object as a HttpApplication instance.

///

/// Called when a cookie is about to be sent to the browser. ///

private void CookieOut(object sender, EventArgs e) { HttpApplication app = (HttpApplication)sender; HttpCookie cookie = app.Response.Cookies["ASP.NET_SessionId"]; if (cookie != null) { app.Response.Cookies.Remove("ASP.NET_SessionId"); cookie.Name = "fooBar"; app.Response.Cookies.Add(cookie); } } read more