The operation has timed out at System.Net.HttpWebRequest.GetResponse() while sending large number of requests to a host
ServicePointManager.DefaultConnectionLimit limits the number of outgoing web requests to a given server. The default is generally 2 or 10. If you are making 50 parallel calls to that web service, you should set ServicePointManager.DefaultConnectionLimit (at app startup) to a larger number (e.g. 40-50). Additionally, you are not calling Close or Dispose on request. You should … Read more