htcheck: 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/htcheck - from package: htcheck

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

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