mftext: 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/mftext - from package: abcmidi

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