I am running a CuteFTP server behind a SonicWall Firewall. All of my clents can connect to my FTP server and send files, except one. I am not sure if the others are using passive or active, but I know that this one can only use active (because that is all their DOS and UNIX clients support). Any rate, they can log in, but basically nothing else, not even LS. They were able to use our third party ftp server, which was hosted on a public IP, but this one, like I said, is behind our SonicWall, which we have opened up for FTP. I can connect to this server fine from home from behind my Netgear Cable-Router/Firewall with active ftp.
I can replicate this problem by ftping to my server via the public address to it from my LAN (the server is in the DMZ). Am I missing something? shouldn't active work?