SFTP Tab

Use Preferred SFTP protocol version to configure maximal version of SFTP protocol that WinSCP will attempt to use. WinSCP will seamlessly downgrade to any lower version that the server supports. The only reason, that you may want to change the option for, is bug either in SFTP server or WinSCP itself specific to particular version of the protocol.

Use Server does not use UTF-8 to configure if WinSCP should use UTF-8 (Unicode) encoding for filenames in communication with the server. With default Auto value, UTF-8 will be used for SFTP protocol 4 and newer, unless the server is known not to support UTF-8 (Foxit software WAC Server). Set the option to On to unconditionally disable usage of UTF-8. Set the option to Off to force usage of UTF-8 (useful for servers using MBCS natively).

The box allows you to configure the bugs WinSCP should expect to see in the SFTP server.

Each bug can be configured in three states. With Off WinSCP will assume that the server does not have the bug. With On WinSCP will assume that the server does have the bug. With Auto (default) WinSCP will try to guess whether or not the server has the bug. The guessing is mostly based on software version string of the SSH server, as most current SFTP servers does announce their software version strings.

WinSCP can work around the bugs of major SFTP servers only. There is many more known bugs in SFTP server implementations. Read more about interoperability with SFTP servers.

The SFTP command to create a symbolic link (symlink) has two arguments: the path the symbolic link should point to and the path of the symlink itself. Some servers incorrectly expects the arguments in reversed order.

If the bug is detected, WinSCP will reverse the order of the arguments too.

The bug is known on SFTP servers shipped with all versions of OpenSSH (bug #861).

While specification for SFTP protocol version 3 and older defines file timestamp to be unsigned 32-bit number representing number of seconds from Jan 1, 1970 in UTC, at least OpenSSH interprets it as signed number. The result is that files on the server with timestamps before 1970 will be interpreted by WinSCP as times after 2038. As it is probably quite common bug, it is currently considered to apply for all servers. Set the option to Off if it does not for your server.

This is SFTP-3 and older specific bug. SFTP-4 introduced signed 64-bit timestamps.