renderpdf: command not found

Have You tried accessing the binary with the full path?

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/bin/renderpdf - from package: libcam-pdf-perl

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