cupsctl: 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/sbin/cupsctl - from package: cups

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

On Debian possible default full paths are:

/usr/sbin/cupsctl - from package: cups-client

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

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