cdfmoy: 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/cdfmoy - from package: cdftools

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