ewfrecover: 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/ewfrecover - from package: ewf-tools

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

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