hamfax: 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/hamfax - from package: hamfax

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

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