Hello, it happens quite often on unix FTP servers that hidden files are not listed. There is an option 'ForceListHiddenFiles' which forces such servers to list also hidden files. Please use it like this:
Ftp ftp = new Ftp();
ftp.Settings.ForceListHiddenFiles = true;
// connect & login
foreach (var item in ftp.GetList())
Does GetList() method return also 'Thumbs.db' now?