I'm having this issue on a specific box, some user are not being able to list folder contant using FTP. Those folder usually have alot of files 50+. If you use IE to ftp in the web root you will be unable to list the content of some folders (not all), If you use a FTP client for exemple like smart ftp or core ftp, it take 3-4 minute sometimes more to list the folder content, but it eventually does. If you use ftp dos command it works like a charm. So one plesk technicien suggested that i needed to have port 20 open (i have the plesk firewall enabled, that is the windows firewall). SO i try that with no luck. So i test and disable the firewall and tada, all works. I haven't got any solution from plesk yet so i'm asking here if anyone has any idea.?