MLSD Fails Through SOCKS? Read the FTP Reply
LIST, MLSD and MLST ask different things; another client's listing success need not reproduce the failing exchange.
Compare both clients' command logs before changing the proxy. LIST supplies server-oriented text; MLSD supplies defined machine-readable directory facts; MLST describes one object.
| Failure | Next check |
|---|---|
| MLSD unrecognized | Server support and client's documented LIST fallback |
| 425 cannot open data connection | PASV/EPSV endpoint and whether that data socket uses SOCKS |
A command fallback addresses format/support, not an unreachable data connection. A successful LIST from another client establishes only that client's chosen command and data path.