There are 2 so did you open both?
" A client opens a connection to the FTP control port (port 21) of an FTP server. So that the server will be later able to send data back to the client machine, a second (data) connection must be opened between the server and the client. "
That is unless you are using PASV.
I am trying to setup 2 seperate ftp site on a windows 2000 server with IIS. For some reason, only port 21 will work. Not a firewall or router problem. I know I need two seperate ports for each ftp site, but only 21 gives me access.
All other ports return an error.