setpdfbackground: 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/setpdfbackground - from package: libcam-pdf-perl

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