apwal: 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/apwal - from package: apwal

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

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