cdfcurl: 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/cdfcurl - from package: cdftools

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