I use ProFTPd as my FTP server which I occasionally run externally to let friends grab files from my home server and to upload content to when I'm away from home. I opt to encrypt both the command and data channels using explicit FTP over TLS and posted about setting this up last year getting ProFTPd working with TLS / SSL. In trying to create a more limited user account with only read only access to a limited number of shared directories I hit a challenge in allowing the user to list the content of the directories when TLS was in place, receiving the error 534 Unwilling to accept security parameters. Here's my solution...
