gdpc: 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/gdpc - from package: gdpc

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

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