mppb: 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/mppb - from package: makepp

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