Get Wireshark on a computer and attach it to a hub between the 400 and the LAN switch. Watch the FTP traffic and you can see in clear text what is happening when doing an FTP session. FTP is not encrypted.
ok…but i am not at the host site, so does the host have to install the Wireshark software?
No, you can install it locally and perform the analysis at your end to see what the conversation looks like between the two hosts.