hio77:ibman9215:chevrolux: You just need to use a non-standard port.
Have a look in 'Management' then 'Access Controls' then 'Remote Access Control List'
The router catches traffic on all those ports. You can't change them so you will have to use a non-standard port to connect to your FTP server.
I've done that using port 1701, still gives the same "Server returned unroutable private IP address in PASV reply" response. Any other ideas?
that reads, as your ftp server is handing out the PASV response, with a private ip. this would indicate a miss configuration in the server itself.. although i would have expected it to be a little more smart about it.
From What I can see, you're right. However, what I'm left wondering is 1. Back when I was on ADSL and used a D-Link modem, everything worked fine, which makes me think the problem is modem related (possibly something to do with NAT), and 2. I'm not sure how to correct it, or even if I can because the FTP server is run by one of Linksys smart wifi routers, which have very basic configuration options.