nopt.js: 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/lib/node_modules/nopt/bin/nopt.js - from package: nodejs-nopt

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

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