pvfmix: 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/pvfmix - from package: mgetty-voice

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

On Debian possible default full paths are:

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

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

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