The Gateway Server attempted to register with ENC Gateway Manager but connection was refused.

This can be caused if the OS Software Firewall is turned on for the involved network and there is no INBOUND exception for port 443 TCP.
 

Any supported ENC environment

The ENC Manager is a special case where both Inbound AND outbound port 443 must be opened as the ENC Client should be able to connect to external ENC Servers via Outbound connection and ENC Server/Router machines must connect to the ENC Manager with an Inbound connection.

The resolution is to create a windows (or applicable Firewall Software) rule to allow incoming traffic on port 443 TCP and activate on the ENC Manager system.

Within a few minutes ENC Server/Router systems should successfully connect to the ENC Manager system.

If not a recycle of CAF on the system(s) should resolve it.