dpkg-reconfigure -fDialog -plow locales
perl: warning: Setting locale failed.
perl: warning: Please check that your locale settings:
        LANGUAGE = (unset),
        LC_ALL = (unset),
        LANG = "fr_FR.UTF-8"
    are supported and installed on your system.
perl: warning: Falling back to the standard locale ("C").
locale: Cannot set LC_CTYPE to default locale: No such file or directory
locale: Cannot set LC_MESSAGES to default locale: No such file or directory
locale: Cannot set LC_ALL to default locale: No such file or directory
debconf: Please do not capitalize the first letter of the debconf frontend.
/usr/sbin/dpkg-reconfigure: locales is broken or not fully installed
root@ns412221:~#