darnwdl: 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/darnwdl - from package: darnwdl

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

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