I have setup FTPS using IIS7 which is working fine. I am using filezilla FTP client to establish the FTP connection. Currently have the FTP client pointing to a single public IP externally which is forwarding requests to the FTP server. The problem i am encountering is port forwarding. If i just forward all traffic from that single public IP to the FTP server, i can establish a connection perfect and upload/downlod files. I need to lock down the firewall but don't know what ports are being used or if i can customize within IIS. The only option i could find was customizing the data port channel range which i did and entered those ports on the firewall along with port 21. This did not work. Below is where filezilla is getting hung up.
Response: 150 Opening BINARY mode data connection.
Error: Connection timed out
Error: Failed to retrieve directory listing