an existing connection was forcibly closed by the remote host. .net core
// If you face error while making inter service call in .net framework. (WEB API 2.0) // user the below code before making an inter service call ServicePointManager.SecurityProtocol = SecurityProtocolType.Tls | SecurityProtocolType.Tls11 | SecurityProtocolType.Tls12; // if want to use existing security protocols with new protocols ServicePointManager.SecurityProtocol |= SecurityProtocolType.Tls | SecurityProtocolType.Tls11 | SecurityProtocolType.Tls12;