[INFO] A simple Windows ACMEv2 client (WACS)
 [INFO] Software version 2.0.10.444 (RELEASE)
 [INFO] IIS not detected
 [WARN] Scheduled task not configured yet
 [INFO] Please report issues at https://github.com/PKISharp/win-acme
 [INFO] Running in mode: Unattended
 [INFO] Target generated using plugin Manual: mydomain.duckdns.org
 [INFO] Authorize identifier: mydomain.duckdns.org
 [INFO] Authorizing mydomain.duckdns.org using http-01 validation (FileSystem)
 [INFO] Answer should now be browsable at http://mydomain.duckdns.org/.well-known/acme-challenge/ya4WpzKzJbJce1WTBqIQjLfjt4Uw35iAv3Olz5nxO4g
 [EROR] Preliminary validation failed
System.Net.WebException: Unable to connect to the remote server ---> System.Net.Sockets.SocketException: No connection could be made because the target machine actively refused it 68.81.215.153:80
   at System.Net.Sockets.Socket.DoConnect(EndPoint endPointSnapshot, SocketAddress socketAddress)
   at System.Net.ServicePoint.ConnectSocketInternal(Boolean connectFailure, Socket s4, Socket s6, Socket& socket, IPAddress& address, ConnectSocketState state, IAsyncResult asyncResult, Exception& exception)
   --- End of inner exception stack trace ---
   at System.Net.HttpWebRequest.GetResponse()
   at PKISharp.WACS.Plugins.ValidationPlugins.HttpValidation`2.WarmupSite()
   at PKISharp.WACS.Plugins.ValidationPlugins.HttpValidation`2.PrepareChallenge()
 [EROR] {
  "type": "urn:ietf:params:acme:error:connection",
  "detail": "Fetching http://mydomain.duckdns.org/.well-known/acme-challenge/ya4WpzKzJbJce1WTBqIQjLfjt4Uw35iAv3Olz5nxO4g: Connection refused",
  "status": 400
}
 [EROR] Authorization result: invalid
 [EROR] Create certificate failed: Authorization failed