target machine actively refused connection/client closed connection

Hi, when I try to connect to my school's server, I get the following message:

[11:13:33] Continue to login attempt 11...
[11:13:33] Resolving host name ""
[11:13:33] Connecting to Port: 21
[11:13:34] No connection could be made because the target machine actively refused it.
[11:13:34] Client closed the connection.
[11:13:34] Active Help:

I see that some other people have had this problem, and based on the advice they received I have already:
1. Checked the IP address
2. Switched from Passive mode to active mode
3. Configured my NIS personal firewall to permit all connections by SmartFTP.

Does anyone have any other ideas???? This is so frustrating.
Thank you.

For premium support please enter your license ID into the forum profile.