Title: Fatal error: call_user_func_array():
Last modified: August 29, 2026

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# Fatal error: call_user_func_array():

 *  Resolved [dtnorz81](https://wordpress.org/support/users/dtnorz81/)
 * (@dtnorz81)
 * [3 weeks ago](https://wordpress.org/support/topic/fatal-error-call_user_func_array-2/)
 * Hi. I recently updated all my plugins. Following that I updated to the latest
   version of WordPress (7.1). After the update I am unable to login and I receive
   the message below. I have replaced my wp-admin and wp-includes folders and I 
   have disabled all of my plugins, but I still receive the following message.
 * Any help on getting the site back up is greatly appreciated. I have access to
   Plesk and PHPMyAdmin.
 * Thank you!
 * **Fatal error**: Uncaught TypeError: call_user_func_array(): Argument #1 ($callback)
   must be a valid callback, function “_wp_register_default_icon_collections” not
   found or invalid function name in G:\PleskVhosts\robinmeadows.com\httpdocs\wp-
   includes\class-wp-hook.php:353 Stack trace: #0 G:\PleskVhosts\robinmeadows.com\
   httpdocs\wp-includes\class-wp-hook.php(377): WP_Hook->apply_filters() #1 G:\PleskVhosts\
   robinmeadows.com\httpdocs\wp-includes\plugin.php(523): WP_Hook->do_action() #
   2 G:\PleskVhosts\robinmeadows.com\httpdocs\wp-settings.php(771): do_action() #
   3 G:\PleskVhosts\robinmeadows.com\httpdocs\wp-config.php(78): require_once(‘…’)#
   4 G:\PleskVhosts\robinmeadows.com\httpdocs\wp-load.php(50): require_once(‘…’)#
   5 G:\PleskVhosts\robinmeadows.com\httpdocs\wp-blog-header.php(13): require_once(‘…’)#
   6 G:\PleskVhosts\robinmeadows.com\httpdocs\index.php(17): require(‘…’) #7 {main}
   thrown in **G:\PleskVhosts\robinmeadows.com\httpdocs\wp-includes\class-wp-hook.
   php** on line **353**
 * The page I need help with: _[[log in](https://login.wordpress.org/?redirect_to=https%3A%2F%2Fwordpress.org%2Fsupport%2Ftopic%2Ffatal-error-call_user_func_array-2%2F%3Foutput_format%3Dmd&locale=en_US)
   to see the link]_

Viewing 3 replies - 1 through 3 (of 3 total)

 *  [Patrick – WPMU DEV Support](https://wordpress.org/support/users/wpmudevsupport12/)
 * (@wpmudevsupport12)
 * [3 weeks ago](https://wordpress.org/support/topic/fatal-error-call_user_func_array-2/#post-19006056)
 * Hi [@dtnorz81](https://wordpress.org/support/users/dtnorz81/)
 * The _wp_register_default_icon_collections seems a recent addition to WordPress:
 * [https://core.trac.wordpress.org/changeset/62748](https://core.trac.wordpress.org/changeset/62748)
 * I suggest trying to reinstall the WordPress core as first step [https://wordpress.org/support/topic/reinstall-wp-from-dashboard/#post-18089828](https://wordpress.org/support/topic/reinstall-wp-from-dashboard/#post-18089828)
 * Best Regards
    Patrick Freitas
 *  Thread Starter [dtnorz81](https://wordpress.org/support/users/dtnorz81/)
 * (@dtnorz81)
 * [3 weeks ago](https://wordpress.org/support/topic/fatal-error-call_user_func_array-2/#post-19006482)
 * Thanks Patrick – I appreciate the reply. I was able to revert back to WordPress
   7.04 and all is well. I guess I will wait a few months for the bugs to be worked
   out on the 7.1 build.
 *  Moderator [threadi](https://wordpress.org/support/users/threadi/)
 * (@threadi)
 * [3 weeks ago](https://wordpress.org/support/topic/fatal-error-call_user_func_array-2/#post-19006507)
 * To me, it sounds more like you’re using a plugin that’s trying to use this new
   feature in WordPress 7.1 – but incorrectly. I’d recommend checking to see which
   one it might be. You can also deactivate all plugins, update to WordPress 7.1,
   and then reactivate the plugins one by one. As soon as the error reappears, you’ll
   have found the culprit plugin. I’ve already successfully used this new feature
   myself.

Viewing 3 replies - 1 through 3 (of 3 total)

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## Tags

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

 * In: [Fixing WordPress](https://wordpress.org/support/forum/how-to-and-troubleshooting/)
 * 3 replies
 * 3 participants
 * Last reply from: [threadi](https://wordpress.org/support/users/threadi/)
 * Last activity: [3 weeks ago](https://wordpress.org/support/topic/fatal-error-call_user_func_array-2/#post-19006507)
 * Status: resolved

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