hxxmlns: 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/hxxmlns - from package: html-xml-utils

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

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