mkelfImage: 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/sbin/mkelfImage - from package: mkelfimage

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

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