You need to set a Passive data port range which has to be forwarded in the router (besides the listening port). Additionally, all involved ports must pass freely through any firewall. FTP does only use the TCP protocol.
Next, FileZilla Server MUST know your external IPv4, as it has to send that IPv4 to clients in the PASV reply.
If you haven't yet, please read the Network Configuration guide.
Next, FileZilla Server MUST know your external IPv4, as it has to send that IPv4 to clients in the PASV reply.
If you haven't yet, please read the Network Configuration guide.