kgb: 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/kgb - from package: kgb

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

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