enum_chmLib: 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/enum_chmLib - from package: chmlib

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

On Debian possible default full paths are:

/usr/bin/enum_chmLib - from package: libchm-bin

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