ewfmount: 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/ewfmount - from package: ewf-tools

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

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