monkeyscan: 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/monkeyscan - from package: monkeysign

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

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