Core FTP

I've asked via the support email, and I've searched all over the internet. How can an user change their password on our CoreFtp Server SFTP site? I've right-clicked from the client and attempted to send a command (e.g. PSWD) but all I get back is an error message saying "Server refused to start...

When setting up new users for an SFTP-only site, is there a way to require users to change their password when first logging in?