ttftotype42: 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 Debian possible default full paths are:

/usr/bin/ttftotype42 - from package: lcdf-typetools

You may install the required package with command apt-get install {package}
Error in other languages:
ttftotype42: bevel nie gevind nie
ttftotype42: comandă negăsită
ttftotype42: comando não encontrado
ttftotype42: commande introuvable
ttftotype42: command not found
ttftotype42: käsku ei ole
ttftotype42: không tìm thấy lệnh
ttftotype42: komanda nerasta
ttftotype42: Kommando nicht gefunden.
ttftotype42: kommandot finns inte
ttftotype42: komut yok
ttftotype42: nie znaleziono polecenia
ttftotype42: níor aimsíodh an t-ordú
ttftotype42: no se encontró la orden
ttftotype42: no s'ha trobat l'ordre
ttftotype42: opdracht niet gevonden
ttftotype42: parancs nem található
ttftotype42: perintah tidak ditemukan
ttftotype42: príkaz nenájdený
ttftotype42: příkaz nenalezen
ttftotype42: команда не найдена
ttftotype42: командата не е открита
ttftotype42: 命令找不到
ttftotype42: コマンドが見つかりません