vbackup: 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/vbackup - from package: vbackup

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

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