gnome-color-chooser: 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/gnome-color-chooser - from package: gnome-color-chooser

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

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