lou_allround: 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/lou_allround - from package: liblouis-bin

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

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