script.mpb: 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"

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