gwu: 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/gwu - from package: geneweb

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

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