elk-bands: 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/elk-bands - from package: elk-lapw

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

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