ao-list: 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/ao-list - from package: altos

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

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