vfgrep: 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/vfgrep - from package: atfs

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

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