hxunxmlns: command not found

Have You tried accessing the binary with the full path?

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/hxunxmlns - from package: html-xml-utils

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