ddccontrol: 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

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/ddccontrol - from package: ddccontrol

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