pw-inspector: 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 CentOS possible default full paths are:

/usr/bin/pw-inspector - from package: hydra

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

On Debian possible default full paths are:

/usr/bin/pw-inspector - from package: hydra

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

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