tdpd: 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/tdpd - from package: tcm

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

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