public override bool CheckAuthentication()
    {
        // WARNING : DO NOT simply return "true". By doing so, you are allowing
        // "anyone" to upload and list the files in your server. You must implement
        // some kind of session validation here. Even something very simple as...
        //
        return (Session["IsAuthorized"] != null && (bool)Session["IsAuthorized"] == true);
        //
        // ... where Session[ "IsAuthorized" ] is set to "true" as soon as the
        // user logs on your system.
        //return true;
    }