问如何启用用于API集成的TLS 1.0权限

EN

  using (var client = new WebClient())
        {
            client.Headers.Add("Authorization", "Bearer " + accessToken);
            string query = "SELECT ID,NAME,LASTMODIFIEDDATE FROM Outage_Schedule_c WHERE IsDeleted = False ORDER BY ID ASC NULLS FIRST".Replace(' ', '+');
            var response = client.DownloadString(instanceUrl + "/services/data/v20.0/query?q=" + query);

            return response ;
        }


 private static string HttpPostRequest(string uri)
   {
       var request = WebRequest.Create(uri);
       request.Method = "POST";
       var resp = request.GetResponse();
       var sr = new System.IO.StreamReader(resp.GetResponseStream());
       return sr.ReadToEnd().Trim();
   }