vfldrvs: 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/bin/vfldrvs - from package: vflib3-bin

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