All of my computer are behind a single router. I have a FileZilla server running on one of them. I am trying to automate an upload to the server using a batch script and Window's built-in ftp.exe. I have set up a dynamic DNS service to be able to access my server from outside the router and I have set up port forwarding in the router to my server. I can connect and transfer just fine using Google Chrome, Windows Explorer, and the FileZilla client. However, whenever I try using ftp.exe (either manually or in batch script) I can connect to the server but if I try doing anything that would open a data connection (LIST, STOR, or RETR) I get the following error: 425 Can't open data connection. I have allowed ftp.exe in both computer's firewalls. Any ideas what is going on or how I could fix it? I don't need to use ftp.exe if anyone knows of a portable independent (just an exe with no other files) command line client.
EDIT I know that my ISP blocks many ports including 21 and several others in that range. This is all set up on port 2121, with the passive ports set up to be 2122-2142, all of these have been forwarded in the router. Perhaps ftp.exe will only use a certain port for data connection, which my ISP blocked? If so how would I change this?