pof7: 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/pof7 - from package: mh-book

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

Error in other languages:
pof7: bevel nie gevind nie
pof7: comandă negăsită
pof7: comando não encontrado
pof7: commande introuvable
pof7: command not found
pof7: käsku ei ole
pof7: không tìm thấy lệnh
pof7: komanda nerasta
pof7: Kommando nicht gefunden.
pof7: kommandot finns inte
pof7: komut yok
pof7: nie znaleziono polecenia
pof7: níor aimsíodh an t-ordú
pof7: no se encontró la orden
pof7: no s'ha trobat l'ordre
pof7: opdracht niet gevonden
pof7: parancs nem található
pof7: perintah tidak ditemukan
pof7: príkaz nenájdený
pof7: příkaz nenalezen
pof7: команда не найдена
pof7: командата не е открита
pof7: 命令找不到
pof7: コマンドが見つかりません