ProcessVX_Unix.pm: 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/lib/ace/bin/PerlACE/ProcessVX_Unix.pm - from package: mpc-ace

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

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