test_files.mpb: 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"

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