defcolors: 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/defcolors - from package: libxgks-dev

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

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