If command line FTP, on Windows 10, is connecting and not allowing items to be downloaded then it may be due to the Windows 10 Firewall blocking incoming connections. When a machine connects with the Active FTP protocol the FTP server makes a separate connection back to the client to transfer the data. This is blocked by default by the Windows Firewall and an exception needs to be added to allow the incoming connection. The following PowerShell command needs to be run as administrator:
New-NetFirewallRule -DisplayName "FTP In" -Direction Inbound -Protocol TCP –Enabled True –Action Allow -Profile Any -Program "%SystemRoot%\System32\ftp.exe" -Service Any -LocalPort 20,21,1024-65535 -EdgeTraversalPolicy Allow
Now the user should be able to connect and download items.