Connection problem

SmartFTP is telling me this:

[00:09:42] SmartFTP v2.0.995.18
[00:09:43] Resolving host name "www.5000megs.com"
[00:09:43] Connecting to 209.144.74.145 Port: 21
[00:09:43] Connected to www.5000megs.com.
[00:09:43] 421 Too many connections (2) from this IP
[00:09:43] Cannot login waiting to retry (30s)...
[00:09:43] An established connection was aborted by the software in your host machine.
[00:09:43] Server closed connection

What is the problem? What does it mean by "too many connections (2)"?
Thank you!

Solved! It was windows firewall.

This is what my log looks like when I attempt a connection.
[23:17:47] Continue to login attempt 8...
[23:17:47] Cannot login waiting to retry (30s)...
[23:18:17] Continue to login attempt 9...
[23:18:17] Cannot login waiting to retry (30s)...
[23:18:47] Continue to login attempt 10...
[23:18:47] Cannot login waiting to retry (30s)...
[23:19:17] Continue to login attempt 11...

And so on. Then it disconnected. This is my first time using Smart. I am used to coming straight out of DreamWeaver so this approach is not familiar to me yet. I have attempted 2 different host connections and neither work. I did view the tutorial for connecting and all is correct to the best of my knowledge. Thank you.