heimdal-strength: command not found

Maybe Your $PATH variable doesn't contain the default paths? echo $PATH should give something like:

[root@server ~]# echo $PATH
/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin

If it's empty, You may set the PATH variable with this command

export PATH="/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin"

On Debian possible default full paths are:

/usr/bin/heimdal-strength - from package: krb5-strength

You may install the required package with command apt-get install {package}

Error in other languages:
heimdal-strength: bevel nie gevind nie
heimdal-strength: comandă negăsită
heimdal-strength: comando não encontrado
heimdal-strength: commande introuvable
heimdal-strength: command not found
heimdal-strength: käsku ei ole
heimdal-strength: không tìm thấy lệnh
heimdal-strength: komanda nerasta
heimdal-strength: Kommando nicht gefunden.
heimdal-strength: kommandot finns inte
heimdal-strength: komut yok
heimdal-strength: nie znaleziono polecenia
heimdal-strength: níor aimsíodh an t-ordú
heimdal-strength: no se encontró la orden
heimdal-strength: no s'ha trobat l'ordre
heimdal-strength: opdracht niet gevonden
heimdal-strength: parancs nem található
heimdal-strength: perintah tidak ditemukan
heimdal-strength: príkaz nenájdený
heimdal-strength: příkaz nenalezen
heimdal-strength: команда не найдена
heimdal-strength: командата не е открита
heimdal-strength: 命令找不到
heimdal-strength: コマンドが見つかりません