w2html: 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/w2html - from package: w2do

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

Error in other languages:
w2html: bevel nie gevind nie
w2html: comandă negăsită
w2html: comando não encontrado
w2html: commande introuvable
w2html: command not found
w2html: käsku ei ole
w2html: không tìm thấy lệnh
w2html: komanda nerasta
w2html: Kommando nicht gefunden.
w2html: kommandot finns inte
w2html: komut yok
w2html: nie znaleziono polecenia
w2html: níor aimsíodh an t-ordú
w2html: no se encontró la orden
w2html: no s'ha trobat l'ordre
w2html: opdracht niet gevonden
w2html: parancs nem található
w2html: perintah tidak ditemukan
w2html: príkaz nenájdený
w2html: příkaz nenalezen
w2html: команда не найдена
w2html: командата не е открита
w2html: 命令找不到
w2html: コマンドが見つかりません