astk: 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/astk - from package: code-aster-gui

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

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