voctopvf: 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 CentOS possible default full paths are:

/usr/bin/voctopvf - from package: mgetty-voice

You may install the required package with command yum install {package}

On Debian possible default full paths are:

/usr/bin/voctopvf - from package: mgetty-pvftools

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

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