miwm: 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/miwm - from package: miwm

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