"error": {
 "errors": [
  {
   "domain": "global",
   "reason": "required",
   "message": "Missing attendee email."
  },
  {
   "domain": "global",
   "reason": "required",
   "message": "Missing attendee email."
  }
 ],
 "code": 400,
 "message": "Missing attendee email."
}

Win 7 /64, Tbird 38.2.0, Lightning 4.0.2 Adding attendees from my address book. Timestamp: 2015-09-12 07:33:07 Error: [calGoogleCalendar] Adding Item johan failed:2147746065: A request Error Occurred. Status Code: 400 Bad Request Body: { "error": { "errors": [ { "domain": "global", "reason": "required", "message": "Missing attendee email." }, { "domain": "global", "reason": "required", "message": "Missing attendee email." } ], "code": 400, "message": "Missing attendee email." } }