econvert: 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/econvert - from package: exactimage

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

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