gpw: 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/gpw - from package: gpw

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

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