GENERAL SFTP SUPPORT IS OFF-TOPIC. Support questions may be asked on https://superuser.com. SSH File Transfer Protocol, a network protocol designed to provide secure file transfer and manipulation facilities over SSH (Secure Shell protocol).
The SSH File Transfer Protocol (also Secret File Transfer Protocol, Secure FTP, or SFTP) is a network protocol that provides file access, file transfer, and file management functionality over any reliable data stream. It was designed by the Internet Engineering Task Force (IETF) as an extension of the Secure Shell protocol (SSH) version 2.0 to provide secure file transfer capability, but is also intended to be usable with other protocols. The IETF of the Internet Draft states that even though this protocol is described in the context of the SSH-2 protocol, it could be used in a number of different applications, such as secure file transfer over Transport Layer Security (TLS) and transfer of management information in VPN applications.
This protocol assumes that it is run over a secure channel, such as SSH, that the server has already authenticated the client, and that the identity of the client user is available to the protocol.
This should not be confused with FTPS. For questions regarding FTPS, see the corresponding tag ftps.
