dumppdf: 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/bin/dumppdf - from package: python-pdfminer

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

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