I can read and write in local network at Mendix(with Opc UA connector module in marketplace) with opc ua server, until doing upload to version control server. but when upload, view app in browser, i tried to connect with opc ua server(external ip). but i got the message. Unable to connect because of error: Connection refused com.mendix.systemwideinterfaces.MendixRuntimeException: com.mendix.core.CoreException: java.util.concurrent.ExecutionException: UaException: status=Bad_ConnectionRejected, message=io.netty.channel.AbstractChannel$AnnotatedConnectException: Connection refused: /192.168.0.67:49320 at com.mendix.basis.actionmanagement.ActionManager.executeSync(ActionManager.scala:108) but external Ip: port is current Listening and remove firewall. How to solve it