ewfinfo: command not found

Have You tried accessing the binary with the full path?

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 CentOS possible default full paths are:

/usr/bin/ewfinfo - from package: ewftools

You may install the required package with command yum install {package}

On Debian possible default full paths are:

/usr/bin/ewfinfo - from package: ewf-tools

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