Ettable: 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/Ettable - from package: eterm

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