Title: Error: call_user_func_array() expects parameter 1
Last modified: March 11, 2018

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# Error: call_user_func_array() expects parameter 1

 *  Resolved [Ahmad Awais](https://wordpress.org/support/users/mrahmadawais/)
 * (@mrahmadawais)
 * [8 years, 2 months ago](https://wordpress.org/support/topic/error-call_user_func_array-expects-parameter-1/)
 * The recent update caused an error and I disabled the plugin.
 * Here’s what it said on a production site where I had no access to the debugging
   tools.
 * `Warning: call_user_func_array() expects parameter 1 to be a valid callback, 
   function '_return_false' not found or invalid function name in /www/site_name.
   com/public/wp-includes/class-wp-hook.php on line 286`

Viewing 2 replies - 1 through 2 (of 2 total)

 *  Plugin Support [WP Compress](https://wordpress.org/support/users/smartersite/)
 * (@smartersite)
 * [8 years, 2 months ago](https://wordpress.org/support/topic/error-call_user_func_array-expects-parameter-1/#post-10062459)
 * Hello Ahmad!
 * Thanks for reporting this issue, we have tested this on debug enabled instance
   and we have not noticed the PHP warning anywhere. Can you please describe at 
   which screen and under which action does the warning show?
 * Thanks!
 *  Plugin Support [WP Compress](https://wordpress.org/support/users/smartersite/)
 * (@smartersite)
 * [8 years, 2 months ago](https://wordpress.org/support/topic/error-call_user_func_array-expects-parameter-1/#post-10091249)
 * Resolved.

Viewing 2 replies - 1 through 2 (of 2 total)

The topic ‘Error: call_user_func_array() expects parameter 1’ is closed to new replies.

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 * 2 replies
 * 2 participants
 * Last reply from: [WP Compress](https://wordpress.org/support/users/smartersite/)
 * Last activity: [8 years, 2 months ago](https://wordpress.org/support/topic/error-call_user_func_array-expects-parameter-1/#post-10091249)
 * Status: resolved