# File lib/openid/consumer/idres.rb, line 258
      def process_check_auth_response(response)
        is_valid = response.get_arg(OPENID_NS, 'is_valid', 'false')

        invalidate_handle = response.get_arg(OPENID_NS, 'invalidate_handle')
        if !invalidate_handle.nil?
          Util.log("Received 'invalidate_handle' from server #{server_url}")
          if @store.nil?
            Util.log('Unexpectedly got "invalidate_handle" without a store!')
          else
            @store.remove_association(server_url, invalidate_handle)
          end
        end

        if is_valid != 'true'
          raise ProtocolError, ("Server #{server_url} responds that the "\
                                "'check_authentication' call is not valid")
        end
      end