gpick: 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/gpick - from package: gpick

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

On Debian possible default full paths are:

/usr/bin/gpick - from package: gpick

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

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