Title: PHP Fatal error – function add()
Last modified: September 1, 2016
---
# PHP Fatal error – function add()
* [Alkerion](https://wordpress.org/support/users/alkerion/)
* (@alkerion)
* [9 years, 11 months ago](https://wordpress.org/support/topic/php-fatal-error-function-add/)
* Hi !
* Here is the error I get :
* `PHP Fatal error: Uncaught Error: Call to a member function add() on null in /
home/clients/3456/web/wp-content/plugins/si-captcha-for-wordpress/si-captcha.
php:656
thrown in /home/clients/3456/web/wp-content/plugins/si-captcha-for-wordpress/
si-captcha.php on line 656 #3 {main} #2 /home/clients/3456/web/wp-login.php(698):
register_new_user(‘nellieseeley13’, ‘margarettapockr…’) #1 /home/clients/3456/
web/wp-includes/user.php(2281): apply_filters(‘registration_er…’, NULL, ‘nellieseeley13’,‘
margarettapockr…’) #0 /home/clients/3456/web/wp-includes/plugin.php(235): siCaptcha-
>si_captcha_register_post(NULL) Stack trace:
* This error seems to be returned when the captcha is inaccurate.
* Any idea what’s going wrong ?
* Thanks
* BR
* Version: 2.7.7.7
* [https://wordpress.org/plugins/si-captcha-for-wordpress/](https://wordpress.org/plugins/si-captcha-for-wordpress/)
Viewing 10 replies - 1 through 10 (of 10 total)
* Thread Starter [Alkerion](https://wordpress.org/support/users/alkerion/)
* (@alkerion)
* [9 years, 11 months ago](https://wordpress.org/support/topic/php-fatal-error-function-add/#post-7544786)
* I also have the same error on two other sites (http and https)
* The error is on that line:
* ```
$errors->add('captcha_error', "$error: $validate_result");
```
* In this function :
* ```
// this function checks the captcha posted with registration
function si_captcha_register_post($errors) {
global $si_captcha_dir, $si_captcha_dir_ns, $si_captcha_opt;
$validate_result = $this->si_captcha_validate_code('reg', 'unlink');
if($validate_result != 'valid') {
$error = ($si_captcha_opt['si_captcha_error_error'] != '') ? $si_captcha_opt['si_captcha_error_error'] : __('ERROR', 'si-captcha');
$errors->add('captcha_error', "$error: $validate_result");
return $errors;
}
return($errors);
} // end function si_captcha_register_post
```
* [mbrsolution](https://wordpress.org/support/users/mbrsolution/)
* (@mbrsolution)
* [9 years, 11 months ago](https://wordpress.org/support/topic/php-fatal-error-function-add/#post-7544899)
* Hi, try the following. Deactivate all your plugins except this one and carry
out a test? If that does not fix the problem try one of WordPress defaults themes
like Twenty Fifteen.
* Thank you
* Thread Starter [Alkerion](https://wordpress.org/support/users/alkerion/)
* (@alkerion)
* [9 years, 7 months ago](https://wordpress.org/support/topic/php-fatal-error-function-add/#post-8311568)
* Hi !
* I’ve never solved this issue on my sites.
* I’ve built a new site and I still have issues with this plugin.
* If the captcha field is empty or inaccurate I obtain the error :
* Error thrown
Call to a member function add() on null
* This time there is no PHP error thrown.
If I enter the right captcha everything
works as expected.
* HELP appreciated.
* Regards
* [mbrsolution](https://wordpress.org/support/users/mbrsolution/)
* (@mbrsolution)
* [9 years, 7 months ago](https://wordpress.org/support/topic/php-fatal-error-function-add/#post-8313475)
* Hi, what PHP version is your server running? I can’t reproduce this error on
my test local site or my test life site.
* Regards
* Thread Starter [Alkerion](https://wordpress.org/support/users/alkerion/)
* (@alkerion)
* [9 years, 7 months ago](https://wordpress.org/support/topic/php-fatal-error-function-add/#post-8314231)
* HI !
* I use PHP 7.0.7
* I’ll try to setup a new site and I’ll check step by step any changes to determine
what’s going wrong.
* Regards
* [mbrsolution](https://wordpress.org/support/users/mbrsolution/)
* (@mbrsolution)
* [9 years, 7 months ago](https://wordpress.org/support/topic/php-fatal-error-function-add/#post-8343131)
* [@alkerion](https://wordpress.org/support/users/alkerion/), can you test the
latest version 2.7.7.8 and report back.
* Thank you
* Thread Starter [Alkerion](https://wordpress.org/support/users/alkerion/)
* (@alkerion)
* [9 years, 7 months ago](https://wordpress.org/support/topic/php-fatal-error-function-add/#post-8343560)
* Hi !
* It still hang, but I don’t think it’s due to your plugin.
* Regards
* [mbrsolution](https://wordpress.org/support/users/mbrsolution/)
* (@mbrsolution)
* [9 years, 7 months ago](https://wordpress.org/support/topic/php-fatal-error-function-add/#post-8343676)
* Hi, what do you think is causing the hanging effect in your site?
* Thread Starter [Alkerion](https://wordpress.org/support/users/alkerion/)
* (@alkerion)
* [9 years, 7 months ago](https://wordpress.org/support/topic/php-fatal-error-function-add/#post-8344583)
* It seems to be the mix between your plugin and “WP-SpamSchield” and “New User
Approve”.
* “New User Approve” seems to be the mess maker.
* [mbrsolution](https://wordpress.org/support/users/mbrsolution/)
* (@mbrsolution)
* [9 years, 7 months ago](https://wordpress.org/support/topic/php-fatal-error-function-add/#post-8345545)
* Okay so you have a plugin conflict, is that correct?
Viewing 10 replies - 1 through 10 (of 10 total)
The topic ‘PHP Fatal error – function add()’ is closed to new replies.
* 
* [SI CAPTCHA Anti-Spam](https://wordpress.org/plugins/si-captcha-for-wordpress/)
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* 10 replies
* 2 participants
* Last reply from: [mbrsolution](https://wordpress.org/support/users/mbrsolution/)
* Last activity: [9 years, 7 months ago](https://wordpress.org/support/topic/php-fatal-error-function-add/#post-8345545)
* Status: not resolved