dtpcd: 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/dtpcd - from package: ion

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

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