Title: Error: array_key_exists() expects parameter 2 to be array
Last modified: February 1, 2019

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# Error: array_key_exists() expects parameter 2 to be array

 *  [critara](https://wordpress.org/support/users/critara/)
 * (@critara)
 * [7 years, 3 months ago](https://wordpress.org/support/topic/error-array_key_exists-expects-parameter-2-to-be-array/)
 * Hi, I am getting this php error since I updated all plugins and WP core.
 * : array_key_exists() expects parameter 2 to be array,null given in /home/***/
   public_html/***/wp-content/plugins/wp-math-captcha/includes/class-core.php on
   line 644
 * Am I the only one finding this error?
    Please advise as to what I should do. 
   Thank you in advance 🙂
 * p.s. great plugin!

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## Tags

 * [php-error](https://wordpress.org/support/topic-tag/php-error/)

 * 0 replies
 * 1 participant
 * Last reply from: [critara](https://wordpress.org/support/users/critara/)
 * Last activity: [7 years, 3 months ago](https://wordpress.org/support/topic/error-array_key_exists-expects-parameter-2-to-be-array/)
 * Status: not resolved