Automatically performs standard server validation to authenticate the server.

For SFTP, the list of known hosts that have been loaded by the client is searched for the server's IP address and hostname. The public key presented by the server is checked for a match against the public keys registered for that host. Note that if the server presents (for example) a DSA key, only a DSA key registered under the hostname or IP address for the server will be able to match. If a matching public key for the server is found, validation succeeds.

For FTPS, operating system resources are used to validate the certificate presented by the server. On Windows the installed certificates are used for this purpose. These certificates may be managed on the Contents tab of the Internet Options control panel.

Note that an important part of validating the certificate is to perform a name-check. In a name-check the Common Name on the certificate is compared with the host-name of the FTP server that we believe we are connected to. The Common Name to be used for name-checking is assumed to be the same as the host-name that was used upon connection, though it may be set manually using the ServerCommonName.