problem z chmode

kiedy chcę ustawić w pliku chmode rw-rw---- dostaję taki błąd
Unable to execute site command chmod 0664 /og/u5. Note that the CHMOD command is only available on Unix FTP servers, not on Windows FTP servers.
Unable to execute site command chmod 0664 /og/u5. Note that the CHMOD command is only available on Unix FTP servers, not on Windows FTP servers.