I've recently had WHM and cPanel installed on my server, and everything works fine except the FTP server. When I log in to any of the cPanel accounts I've created, it all works fine until my FTP program issues the LIST command (basically the FTP command which runs the Linux command 'ls').

This doesn't happen all of the time. For instance, it might work in loading the first directory you see when you log in, but it might not work when I try to open a subdirectory within that. When it does freeze though, the connection times out.

I have all ports from 20000 upwards open on TCP and UDP in both directions on my firewall.

Any ideas as to what might be wrong? Thanks.