eTktab: 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/eTktab - from package: etktab

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

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