FTP files?

I'm not sure if I'm in the right forum, but is anyone able to help me use Firefox FTP files? I have downloaded Moxilla and Firefox FTP, but when it asks for my login information, nothing happens. Could this be a firewall issue? The last time I messed with my firewall I got a virus. I have been trying to troubleshoot this problem for hours and think it might be something really simple that I have overlooked. Thank you! Pugmum