Filezilla FTP Server Fails to Retrieve Directory Listing

Most of the answers here involves configuring, actually just by adding sftp:// on your host (see below image) you can instantly fixed that kind of problem, works for me.

And also take note that if you follow Vaggelis guide you are lowering your security, sftp is better than using plain ftp.

I just changed the encryption from "Use explicit FTP over TLS if available" to "Only use plain FTP" (insecure) at site manager and it works!

File > Site Manager > Select your site > Transfer Settings > Active

Works for me.

I just changed the encryption from "Use explicit FTP over TLS if available" to "Only use plain FTP" (insecure) at site manager and it works!

When you send the port command to your server, you are asking the server to connect to you (on the remote network). If the remote network also has a NAT router, and you have not port-forwarded the port you are sending with your PORT command, the server will not be able reach you.

The most common solution would be to send the PASV command to the server instead of the PORT command. The PASV command will ask the server to create a listening socket and accept a connection from the remote machine to establish the data connection.

For the PASV command to work, you will also need to port-forward a range of ports for the passive data connections. The passive connection ports (which need to be forwarded) should be listed in the FileZilla documentation.