promlk: 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/lib/phylip/bin/promlk - from package: phylip

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

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