2 FTP problems

I've set-up an FTP server on my PC and I've done port forwarding properly according to portforward.com and have encountered two big problems. The first problem is when I type FTP://192.168.1.100 just to make sure the server is up and running correctly I get a login pop-up and put in the user information but when I click Ok I get an error message saying "A connection with the server could not be established". And to try and see if my port forwarding at least was working, I type FTP://(My external IP) and it doesn't give me the login pop-up that it did when I typed my computers IP thats running the server, it just says "The connection with the server was reset". I'm running Quick and easy FTP server and have also tried Cerberus and some other "Personal Use" and free FTP servers. And I've properly ridded my computer of the old ftp server before I tried a new one so thats irrelevant. No FTP server have worked for me so obviously I'm doing something wrong. I've looked for solutions and tutorials and followed directions exactly and when that didn't work I just experimented with setting, both with no results. I was wondering if anyone could think of something. I am on 2 routers but still that doesn't matter because I tried directly to a single router and that didn't work either. What might I be doing wrong?

(Update) In command line when I ftp my external IP I get this=

Ftp (My external IP)
Connected to (my external IP)
Connection closed by remote host.

Does the ftp server log say anything? can you get it working well from local network? from what you said, it sounded like this scenario did not work either.