lib/protocols/wns.js
function (err, res) {
    if (err) return sender.emit('transmissionError', err, data.channelURI);
    sender.emit('transmitted', res, data.channelURI);
  }
function (err, res) {
    if (err) return sender.emit('transmissionError', err, data.channelURI);
    sender.emit('transmitted', res, data.channelURI);
  }
called once done of is there was a transmission error