pdfclose: 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/pdfclose - from package: texlive-binaries

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

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