pdf180: 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/pdf180 - from package: pdfjam

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

On Debian possible default full paths are:

/usr/bin/pdf180 - from package: texlive-extra-utils

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

Error in other languages:
pdf180: bevel nie gevind nie
pdf180: comandă negăsită
pdf180: comando não encontrado
pdf180: commande introuvable
pdf180: command not found
pdf180: käsku ei ole
pdf180: không tìm thấy lệnh
pdf180: komanda nerasta
pdf180: Kommando nicht gefunden.
pdf180: kommandot finns inte
pdf180: komut yok
pdf180: nie znaleziono polecenia
pdf180: níor aimsíodh an t-ordú
pdf180: no se encontró la orden
pdf180: no s'ha trobat l'ordre
pdf180: opdracht niet gevonden
pdf180: parancs nem található
pdf180: perintah tidak ditemukan
pdf180: príkaz nenájdený
pdf180: příkaz nenalezen
pdf180: команда не найдена
pdf180: командата не е открита
pdf180: 命令找不到
pdf180: コマンドが見つかりません