I have, both on my old version of WINSCP and the new version (4.3.2 build 428), experienced the same error. It is after I make connection, I get an error box with a title 'error listing directory "/"'. Below in the box is the text
"Could not retrieve directory listing
ORT not understood"
I run the program in commander mode, in FTP mode, and this problem only occurs with the one site, <invalid hyperlink removed by admin>. This site is on bulkregister server.
I have no problem going to this site with flashfxp. When I look at its log, I do not see the command "ORT".