rpm2html: 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/rpm2html - from package: rpm2html

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

Error in other languages:
rpm2html: bevel nie gevind nie
rpm2html: comandă negăsită
rpm2html: comando não encontrado
rpm2html: commande introuvable
rpm2html: command not found
rpm2html: käsku ei ole
rpm2html: không tìm thấy lệnh
rpm2html: komanda nerasta
rpm2html: Kommando nicht gefunden.
rpm2html: kommandot finns inte
rpm2html: komut yok
rpm2html: nie znaleziono polecenia
rpm2html: níor aimsíodh an t-ordú
rpm2html: no se encontró la orden
rpm2html: no s'ha trobat l'ordre
rpm2html: opdracht niet gevonden
rpm2html: parancs nem található
rpm2html: perintah tidak ditemukan
rpm2html: príkaz nenájdený
rpm2html: příkaz nenalezen
rpm2html: команда не найдена
rpm2html: командата не е открита
rpm2html: 命令找不到
rpm2html: コマンドが見つかりません