HtFileType: 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 CentOS possible default full paths are:

/usr/bin/HtFileType - from package: htdig

You may install the required package with command yum install {package}

On Debian possible default full paths are:

/usr/bin/HtFileType - from package: htdig

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