cdfsstconv: 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/cdfsstconv - from package: cdftools

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

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