// DocumentNOW V2 CancelEnvelope example  // force TLS 1.2 if .net < 4.6 ServicePointManager.SecurityProtocol = System.Net.SecurityProtocolType.Tls12; 	 Guid accountContextID = new Guid(<fromYourAccount>); Guid envelopeId = new Guid(<fromCreateEnvelope>); Guid authToken = new Guid(<fromCreateEnvelope>);  // assuming we set the namespace on the service proxy to DocNow ... DocNow.EnvelopeServiceClient client = new DocNow.EnvelopeServiceClient("BasicHttpBinding_IEnvelopeService1"); DocNow.CancelEnvelopeRequest request = new DocNow.CancelEnvelopeRequest();  request.ContextIdentifier = accountContextID; request.EnvelopeId = envelopeId request.AuthToken = authToken; request.Remarks = "Cancelling because of so and so ...";  DocNow.CancelEnvelopeResult result = client.CancelEnvelope(request);  if (result.Exceptions != null) {     StringBuilder sb = new StringBuilder();     foreach (DocNow.EnvelopeException exception in result.Exceptions)     {         sb.AppendFormat("{0} : {1}{2}", exception.Severity.ToString(), exception.Value, Environment.NewLine);     }     Console.WriteLine(sb.ToString()); } else {     // the result will return back result.EnvelopeId as confirmation }