Core FTP

Let's say my friend is trying to get through to me, but I have multiple computers behind the router, each with forwarded ports? How does the system know wheichh machine to connect to if we all share the same external IP address?

Can't establishh connection, an existing connection was forcibly closed by the remote host.

any ideas?

Should I forward port 20 also, or is that one already open as a default?

I didn't know about port 20 as part of the FTP process till I read this:

http://en.wikipedia.org/wiki/Ftp#Overview

I am able to connect to my Dad's Mac just fine on this PC, so I guess I can connect out, just not to my friend's machine... nor he to mine. I'll read thru that post

not to one another's machine.

Could the fact that I'm running XP sercie Pack 1 be part of the problem?

Although I have to use another FTP client, I have figured out how to FTP from Mac to Mac. Now I want to do the same from PC to PC with CoreFTP. Unfortunately I can't get into my friends computer, nor he into mine. We have both forwarded ports 21 and 22 to our repective routers and created guest acco...