doc2pdf: 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/doc2pdf - from package: unoconv

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

Error in other languages:
doc2pdf: bevel nie gevind nie
doc2pdf: comandă negăsită
doc2pdf: comando não encontrado
doc2pdf: commande introuvable
doc2pdf: command not found
doc2pdf: käsku ei ole
doc2pdf: không tìm thấy lệnh
doc2pdf: komanda nerasta
doc2pdf: Kommando nicht gefunden.
doc2pdf: kommandot finns inte
doc2pdf: komut yok
doc2pdf: nie znaleziono polecenia
doc2pdf: níor aimsíodh an t-ordú
doc2pdf: no se encontró la orden
doc2pdf: no s'ha trobat l'ordre
doc2pdf: opdracht niet gevonden
doc2pdf: parancs nem található
doc2pdf: perintah tidak ditemukan
doc2pdf: príkaz nenájdený
doc2pdf: příkaz nenalezen
doc2pdf: команда не найдена
doc2pdf: командата не е открита
doc2pdf: 命令找不到
doc2pdf: コマンドが見つかりません