htntlm: 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/htntlm - from package: httest

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

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