vdm_decode: 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/vdm_decode - from package: vdmfec

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

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