chilight: command not found

Have You tried accessing the binary with the full path?

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/chilight - from package: cutils

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