I've been trying all day to set up an FTP server, and keep running into issues.

I'm running Filezilla Server on my PC Desktop, and I've been trying to access it over my university's network (which I think is probably the problem here) over the Filezilla and FireFTP clients on my macbook. I've added port exceptions to my firewall, but I keep getting the 425 "Can't open data connection" error. I don't know if it's relevant, but I have no problem accessing my web server? Anyone have any advice? :/