I have an FTP client that keeps getting a "500 Syntax error, command unrecognized." from the FTP server.
With Windows Firewall enabled (On the client) I get a truncated PORT command at the server. "ORT x,x,x,x,19,137" and which the server promptly replies with unrecognized command.
I've been able to get around the error by disabling Windows Firewall (On the client) and then the "PORT" command is successfully received by the server "PORT x,x,x,x,111,228", then FTP works fine and I can do file transfers like normal.
I've tried opening TCP and UDP ports in the range of "5001-5050" (On the client), (If you do the math on "19,137", 5001 is the port it first tries to work on) with no success unless I completely disable the Windows Firewall and then the first port it tries starts at "28644".
So, what settings do I need to change on the Windows firewall (On the client end) so this doesn't happen? Also note that I have many other clients out there nationwide that works fine with same FTP client version communicating with the same FTP server, it's only localized to this one client.
Also note the FTP server is Filezilla and the client is a in-house written FTP client.
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