3dldf: 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/3dldf - from package: 3dldf

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

Error in other languages:
3dldf: bevel nie gevind nie
3dldf: comandă negăsită
3dldf: comando não encontrado
3dldf: commande introuvable
3dldf: command not found
3dldf: käsku ei ole
3dldf: không tìm thấy lệnh
3dldf: komanda nerasta
3dldf: Kommando nicht gefunden.
3dldf: kommandot finns inte
3dldf: komut yok
3dldf: nie znaleziono polecenia
3dldf: níor aimsíodh an t-ordú
3dldf: no se encontró la orden
3dldf: no s'ha trobat l'ordre
3dldf: opdracht niet gevonden
3dldf: parancs nem található
3dldf: perintah tidak ditemukan
3dldf: príkaz nenájdený
3dldf: příkaz nenalezen
3dldf: команда не найдена
3dldf: командата не е открита
3dldf: 命令找不到
3dldf: コマンドが見つかりません