network: 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/lib/plainbox-providers-1/checkbox/bin/network - from package: plainbox-provider-checkbox

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

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