Secure File Transfer Protocol (SFTP) is a component of the Secure Shell (SSH) network service and provides an encrypted method for transferring files over public networks. The password for an SFTP account is directly tied to the user attempting to log in, therefore changing the user password is as simple as logging in to SSH and changing the account password through the standard shell commands. SSH and SFTP are most commonly found on UNIX-like machines, but there are ports for some Windows systems.
Launch a command prompt or terminal window. Most users access SSH from the command line, but if you use a graphical client just ignore the "ssh" prefix of console commands and enter the information into the appropriate fields of your graphical client.
Type "ssh user@server" where "user" is your User name and "server" is the domain name or IP address where the SFTP and SSH server are hosted. Press "Enter" to execute the command and query the server for information. If this is your first time logging in to this server, you will need to accept the encryption certificate.
Enter the password for your user name when prompted. This will complete the connection and provide you with a user shell.
Type "passwd" and press the "Enter" key to start the password changing program. Entr your current password once, then your new password twice. Once you are finished, type "exit" and press the "Enter" key to log out of the SSH server.