cdfbottomsig: 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/cdfbottomsig - from package: cdftools

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

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