Title: Fatal Error
Last modified: August 28, 2023

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# Fatal Error

 *  Resolved [emrieurteaga](https://wordpress.org/support/users/emrieurteaga/)
 * (@emrieurteaga)
 * [2 years, 9 months ago](https://wordpress.org/support/topic/fatal-error-4530/)
 * I keep receiving emails about a fatal error with my WooCommerce plug in. I can’t
   seem to locate the issue, as everything seems okay from the front end. Any ideas
   as to what this could be? Here is the message I received: When seeking help with
   this issue, you may be asked for some of the following information:
   WordPress
   version 6.3Active theme: Aasta Pro (version 2.2)Current plugin: WooCommerce (
   version 8.0.2) PHP version 8.1.21
 * Error Details
   =============An error of type E_ERROR was caused in line 3619 of
   the file /var/www/wp-content/plugins/woocommerce/includes/class-wc-ajax.php. 
   Error message: Uncaught TypeError: WC_AJAX::order_refresh_lock(): Return value
   must be of type array, null returned in /var/www/wp-content/plugins/woocommerce/
   includes/class-wc-ajax.php:3619Stack trace:#0 /var/www/wp-content/plugins/woocommerce/
   includes/class-wc-ajax.php(210): WC_AJAX::order_refresh_lock(NULL, Array)#1 /
   var/www/wp-includes/class-wp-hook.php(312): WC_AJAX::{closure}(NULL, Array)#2/
   var/www/wp-includes/plugin.php(205): WP_Hook->apply_filters(NULL, Array)#3 /var/
   www/wp-admin/includes/ajax-actions.php(3494): apply_filters(‘heartbeat_recei…’,
   Array, Array, ‘product’)#4 /var/www/wp-includes/class-wp-hook.php(310): wp_ajax_heartbeat(”)#
   5 /var/www/wp-includes/class-wp-hook.php(334): WP_Hook->apply_filters(”, Array)#
   6 /var/www/wp-includes/plugin.php(517): WP_Hook->do_action(Array)#7 /var/www/
   wp-admin/admin-ajax.php(188): do_action(‘wp_ajax_heartbe…’)#8 {main} thrown

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

 *  [Owadud](https://wordpress.org/support/users/owadud655/)
 * (@owadud655)
 * [2 years, 9 months ago](https://wordpress.org/support/topic/fatal-error-4530/#post-17008276)
 * Hi,
   The error message you’ve received indicates that there’s a fatal error occurring
   in the WooCommerce plugin on your WordPress site. The specific error you’re encountering
   relates to a TypeError in the WC_AJAX class file. It seems like there’s a problem
   with the `order_refresh_lock` function in the WooCommerce AJAX class.
 * Here are a few steps you can take to troubleshoot and resolve the issue:
    1. **Check for Plugin Conflicts**: Deactivate all other plugins except WooCommerce
       and see if the issue persists. If the error disappears, it might be caused by
       a conflict with another plugin. You can then reactivate the plugins one by one
       to identify the problematic one.
    2. **Switch to a Default Theme**: Temporarily switch your theme to a default WordPress
       theme like Twenty Twenty-One and see if the error still occurs. If it doesn’t,
       the issue might be related to your current theme.
    3. **Update WooCommerce**: Ensure that you’re using the latest version of WooCommerce.
       Sometimes, plugin updates include bug fixes that can resolve such issues.
    4. **PHP Compatibility**: Check if your plugins and theme are compatible with PHP
       8.1. While PHP 8.1 is generally compatible with WordPress, some plugins or themes
       might have issues.
 * Remember to always back up your site before making any major changes, like deactivating
   plugins or switching themes, to ensure you can easily revert if needed.
 *  [hrn1995 (woo-hc)](https://wordpress.org/support/users/aguinaldodarla/)
 * (@aguinaldodarla)
 * [2 years, 9 months ago](https://wordpress.org/support/topic/fatal-error-4530/#post-17015760)
 * Hi [@emrieurteaga](https://wordpress.org/support/users/emrieurteaga/)
 * I suggest running a conflict test to identify it this is a theme or a plugin 
   conflict. [You can find a more detailed explanation on how to do a conflict test here](https://docs.woocommerce.com/document/how-to-test-for-conflicts/).
 * Let us know how it goes! 
   Cheers,

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

The topic ‘Fatal Error’ is closed to new replies.

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 * 3 replies
 * 3 participants
 * Last reply from: [hrn1995 (woo-hc)](https://wordpress.org/support/users/aguinaldodarla/)
 * Last activity: [2 years, 9 months ago](https://wordpress.org/support/topic/fatal-error-4530/#post-17015760)
 * Status: resolved