No connection could be made because the target machine actively refused it. This happens either when trying to connect to an inactive service or when a service process is not present at the requested address.
Activate the service on the target machine, or start it up again if it has disappeared. If, for security reasons, you do not intend to provide this service, inform the user community, possibly suggesting an alternative.
The symbolic name for this error is ECONNREFUSED, errno=146.