vdispatch-conf: command not found

Have You tried accessing the binary with the full path?

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/sbin/vdispatch-conf - from package: util-vserver

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