mk_fol_names.install: 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/share/doc/mh-book/examples/mh/bin/mk_fol_names.install - from package: mh-book

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

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