njb-getfile: command not found

Have You tried accessing the binary with the full path?

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/njb-getfile - from package: libnjb-tools

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