aldo: 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/aldo - from package: aldo

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