A PHP Error was encountered

Severity: Notice

Message: Trying to access array offset on value of type null

Filename: controllers/Simple_php_captcha.php

Line Number: 17

Backtrace:

File: /volume1/web/www.fulgentdot.com.tw/application/controllers/Simple_php_captcha.php
Line: 17
Function: _error_handler

File: /volume1/web/www.fulgentdot.com.tw/index.php
Line: 315
Function: require_once