wmnut: 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"

On Debian possible default full paths are:

/usr/bin/wmnut - from package: wmnut

You may install the required package with command apt-get install {package}

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