afterstep: 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/afterstep - from package: afterstep

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

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