Problems logging on with ftp

I've had problems logging on to a friend's ftp server now that he changed ports. He used to be with port 81 and now he's using other more rare ports due to hacker attacks.

I'm accessing his server through a proxy on my side. I've never had to enter any information regarding the proxy in the setting in the ftp and its worked fine. But now with the new port I manage to access the server fine, but when it attempts to list the directory I get a timeout and port connection closed. Could this be something on my side or settings? Do I need to do something regarding the proxy??

Find the setting in your FTP client which sets whether to use passive (also referred to as PASV) or active mode, and try toggling that.

If that doesn't work, what proxy are you behind, and what client are you using?

I'm using MS proxy and the client is cute FTP. I tried PASV mode and the logon sequence is worse. It doesn't even get as far as the normal way.

I don't know what else to suggest, sorry. The FTP control connection is obviously opening fine, and it's the data connection (for the directory list) that's timing out. Thing is, the port used for that data connection is arbitrary, and doesn't relate to the port you initially connect on. I'm stumped.