WS_FTP - Error: 426 Connection closed; transfer aborted

Question/Problem: I'm receiving the message, "426 Connection closed; transfer aborted". The problem is I don't really understand what causes it or how to rectify the situation.

Answer/Solution: See if you get the same error when you connect with the command line ftp client. If you do not get the error in the command line ftp client, then disable "Passive Mode" in the Connection properties window in WS_FTP.

Go to a DOS prompt (Start->Programs->DOS Prompt)
Connect to the site using the following syntax:
ftp the.hostname.com (or IP_address.)

Once successfully connected, you will be prompted for your username and
password. Enter your username and password and then type "dir" to make
sure that you successfully get a directory listing from the remote site.
Once you get a directory listing, (and once you cd to the directory you want on the ftp server),

to upload a file:
put c:/local_path/filename (enter the exact path of the file that you want to upload here)

to download a file from the ftp server:
get filename (a file that you can see in the directory listing)

If you get the same error in the command line ftp, then the problem is not in WS_FTP. There may be a local firewall blocking the connection or a problem with your ISP's network.