gd2copypal: 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 CentOS possible default full paths are:

/usr/bin/gd2copypal - from package: gd-progs

You may install the required package with command yum install {package}

On Debian possible default full paths are:

/usr/bin/gd2copypal - from package: libgd-tools

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

Error in other languages:
gd2copypal: bevel nie gevind nie
gd2copypal: comandă negăsită
gd2copypal: comando não encontrado
gd2copypal: commande introuvable
gd2copypal: command not found
gd2copypal: käsku ei ole
gd2copypal: không tìm thấy lệnh
gd2copypal: komanda nerasta
gd2copypal: Kommando nicht gefunden.
gd2copypal: kommandot finns inte
gd2copypal: komut yok
gd2copypal: nie znaleziono polecenia
gd2copypal: níor aimsíodh an t-ordú
gd2copypal: no se encontró la orden
gd2copypal: no s'ha trobat l'ordre
gd2copypal: opdracht niet gevonden
gd2copypal: parancs nem található
gd2copypal: perintah tidak ditemukan
gd2copypal: príkaz nenájdený
gd2copypal: příkaz nenalezen
gd2copypal: команда не найдена
gd2copypal: командата не е открита
gd2copypal: 命令找不到
gd2copypal: コマンドが見つかりません