In some networks, it may be necessary to place the SSL-VPN Appliance behind a firewall that has been configured for port-forwarding to a port other than the default TCP 80 (HTTP) and TCP 443 (HTTPS) that run on the SSL-VPN Appliance, as there are many networks where there is only a single public WAN IP Address available, but multiple servers behind the firewall that need access from the Internet.
To run the SSLVPN on a different port from the default 4433, you can follow these steps:
Go to SSLVPN | Server Settings
Modify the "SSLVPN Port" with your custom port.
Note: If you want to use port 443, you have to first change the Management Port (System | Administration | HTTPS Port:)
After this change, you will be able to connect to the SSLVPN using NetExtender or the web browser or Mobile Connect on the port you specified in SSLVPN Port.