pdf2htmlEX: 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/pdf2htmlEX - from package: pdf2htmlex

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

Error in other languages:
pdf2htmlEX: bevel nie gevind nie
pdf2htmlEX: comandă negăsită
pdf2htmlEX: comando não encontrado
pdf2htmlEX: commande introuvable
pdf2htmlEX: command not found
pdf2htmlEX: käsku ei ole
pdf2htmlEX: không tìm thấy lệnh
pdf2htmlEX: komanda nerasta
pdf2htmlEX: Kommando nicht gefunden.
pdf2htmlEX: kommandot finns inte
pdf2htmlEX: komut yok
pdf2htmlEX: nie znaleziono polecenia
pdf2htmlEX: níor aimsíodh an t-ordú
pdf2htmlEX: no se encontró la orden
pdf2htmlEX: no s'ha trobat l'ordre
pdf2htmlEX: opdracht niet gevonden
pdf2htmlEX: parancs nem található
pdf2htmlEX: perintah tidak ditemukan
pdf2htmlEX: príkaz nenájdený
pdf2htmlEX: příkaz nenalezen
pdf2htmlEX: команда не найдена
pdf2htmlEX: командата не е открита
pdf2htmlEX: 命令找不到
pdf2htmlEX: コマンドが見つかりません