Sometimes the message is different. I think it depends on the recipient server. Trying to scp to a dropbear ssh server on a router gives sh: /opt/libexec/sf

Sometimes the message is different. I think it depends on the recipient server. Trying to scp to a dropbear ssh server on a router gives sh: /opt/libexec/sftp-server: not found scp: Connection closed The -O resolution works.