ps2pdf12: 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/ps2pdf12 - from package: ghostscript

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

On Debian possible default full paths are:

/usr/bin/ps2pdf12 - from package: ghostscript

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

Error in other languages:
ps2pdf12: bevel nie gevind nie
ps2pdf12: comandă negăsită
ps2pdf12: comando não encontrado
ps2pdf12: commande introuvable
ps2pdf12: command not found
ps2pdf12: käsku ei ole
ps2pdf12: không tìm thấy lệnh
ps2pdf12: komanda nerasta
ps2pdf12: Kommando nicht gefunden.
ps2pdf12: kommandot finns inte
ps2pdf12: komut yok
ps2pdf12: nie znaleziono polecenia
ps2pdf12: níor aimsíodh an t-ordú
ps2pdf12: no se encontró la orden
ps2pdf12: no s'ha trobat l'ordre
ps2pdf12: opdracht niet gevonden
ps2pdf12: parancs nem található
ps2pdf12: perintah tidak ditemukan
ps2pdf12: príkaz nenájdený
ps2pdf12: příkaz nenalezen
ps2pdf12: команда не найдена
ps2pdf12: командата не е открита
ps2pdf12: 命令找不到
ps2pdf12: コマンドが見つかりません