Fehlermeldung

perl: warning: Setting locale failed.
perl: warning: Please check that your locale settings:
LANGUAGE = "en_US:en",
LC_ALL = (unset),
LC_TIME = "de_AT.UTF-8",
LC_MONETARY = "de_AT.UTF-8",
LC_ADDRESS = "de_AT.UTF-8",
LC_TELEPHONE = "de_AT.UTF-8",
LC_NAME = "de_AT.UTF-8",
LC_MEASUREMENT = "de_AT.UTF-8",
LC_IDENTIFICATION = "de_AT.UTF-8",
LC_NUMERIC = "de_AT.UTF-8",
LC_PAPER = "de_AT.UTF-8",
LANG = "en_US.UTF-8"
are supported and installed on your system.
perl: warning: Falling back to the standard locale ("C").
locale: Cannot set LC_ALL to default locale: No such file or directory

Lösung

locale-gen de_AT.UTF-8
dpkg-reconfigure locales