qmqpfront-echo: 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/sbin/qmqpfront-echo - from package: mailfront

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