Title: Error Message on PHP 8.1
Last modified: August 11, 2022

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# Error Message on PHP 8.1

 *  Resolved [richardchagonda](https://wordpress.org/support/users/richardchagonda/)
 * (@richardchagonda)
 * [3 years, 9 months ago](https://wordpress.org/support/topic/error-message-on-php-8-1/)
 * Hi There
 * Please help with the below error message. We get it when we upgrade to PHP 8.1.
 * `WordPress version 6.0.1 Active theme: My Listing Child (version 1.1) Current
   plugin: Facebook for WordPress (version 3.0.7) PHP version 8.1.8 Error Details
   ============= An error of type E_ERROR was caused in line 42 of the file /usr/
   www/users/yourpepsuh/content/plugins/official-facebook-pixel/vendor/facebook/
   php-business-sdk/src/FacebookAds/Object/ServerSide/Normalizer.php. Error message:
   Uncaught TypeError: strlen(): Argument #1 ($string) must be of type string, array
   given in /usr/www/users/yourpepsuh/content/plugins/official-facebook-pixel/vendor/
   facebook/php-business-sdk/src/FacebookAds/Object/ServerSide/Normalizer.php:42
   Stack trace: #0 /usr/www/users/yourpepsuh/content/plugins/official-facebook-pixel/
   vendor/facebook/php-business-sdk/src/FacebookAds/Object/ServerSide/Normalizer.
   php(42): strlen(Array) #1 /usr/www/users/yourpepsuh/content/plugins/official-
   facebook-pixel/vendor/facebook/php-business-sdk/src/FacebookAds/Object/ServerSide/
   UserData.php(914): FacebookAds\Object\ServerSide\Normalizer::normalize('em', 
   Array) #2 /usr/www/users/yourpepsuh/content/plugins/official-facebook-pixel/vendor/
   facebook/php-business-sdk/src/FacebookAds/Object/ServerSide/UserData.php(863):
   FacebookAds\Object\ServerSide\UserData->normalizeHashDedup('em', Array) #3 /usr/
   www/users/yourpepsuh/content/plugins/official-facebook-pixel/vendor/facebook/
   php-business-sdk/src/FacebookAds/Object/ServerSide/Event.php(373): FacebookAds\
   Object\ServerSide\UserData->normalize() #4 /usr/www/users/yourpepsuh/content/
   plugins/official-facebook-pixel/vendor/facebook/php-business-sdk/src/FacebookAds/
   Object/ServerSide/EventRequest.php(302): FacebookAds\Object\ServerSide\Event-
   >normalize() #5 /usr/www/users/yourpepsuh/content/plugins/official-facebook-pixel/
   vendor/facebook/php-business-sdk/src/FacebookAds/Object/ServerSide/EventRequest.
   php(240): FacebookAds\Object\ServerSide\EventRequest->normalize() #6 /usr/www/
   users/yourpepsuh/content/plugins/official-facebook-pixel/vendor/facebook/php-
   business-sdk/src/FacebookAds/Object/ServerSide/EventRequest.php(235): FacebookAds\
   Object\ServerSide\EventRequest->defaultExecute() #7 /usr/www/users/yourpepsuh/
   content/plugins/official-facebook-pixel/core/FacebookServerSideEvent.php(108):
   FacebookAds\Object\ServerSide\EventRequest->execute() #8 /usr/www/users/yourpepsuh/
   content/plugins/official-facebook-pixel/core/ServerEventAsyncTask.php(147): FacebookPixelPlugin\
   Core\FacebookServerSideEvent::send(Array) #9 /usr/www/users/yourpepsuh/content/
   plugins/official-facebook-pixel/vendor/techcrunch/wp-async-task/wp-async-task.
   php(164): FacebookPixelPlugin\Core\ServerEventAsyncTask->run_action() #10 /usr/
   www/users/yourpepsuh/wp-includes/class-wp-hook.php(307): WP_Async_Task->handle_postback('')#
   11 /usr/www/users/yourpepsuh/wp-includes/class-wp-hook.php(331): WP_Hook->apply_filters('',
   Array) #12 /usr/www/users/yourpepsuh/wp-includes/plugin.php(476): WP_Hook->do_action(
   Array) #13 /usr/www/users/yourpepsuh/wp-admin/admin-post.php(61): do_action('
   admin_post_nopr...') #14 {main} thrown`

Viewing 1 replies (of 1 total)

 *  [Rafy](https://wordpress.org/support/users/nawaz0705/)
 * (@nawaz0705)
 * [3 years, 9 months ago](https://wordpress.org/support/topic/error-message-on-php-8-1/#post-15908356)
 * Hi [@richardchagonda](https://wordpress.org/support/users/richardchagonda/)
 * Thank you for reaching out!
 * It seems that you are using the [Facebook for WordPress](https://wordpress.org/plugins/official-facebook-pixel/)
   plugin and the errors are related to this particular plugin.
 * You can temporarily deactivate that plugin to see if you are still seeing the
   error.
 * If you want to connect your WooCommerce store to Facebook, I would suggest using
   our [Facebook for WooCommerce](https://wordpress.org/plugins/facebook-for-woocommerce/)
   plugin.
 * I hope this helps!

Viewing 1 replies (of 1 total)

The topic ‘Error Message on PHP 8.1’ is closed to new replies.

 * ![](https://ps.w.org/facebook-for-woocommerce/assets/icon.svg?rev=3469606)
 * [Meta for WooCommerce](https://wordpress.org/plugins/facebook-for-woocommerce/)
 * [Support Threads](https://wordpress.org/support/plugin/facebook-for-woocommerce/)
 * [Active Topics](https://wordpress.org/support/plugin/facebook-for-woocommerce/active/)
 * [Unresolved Topics](https://wordpress.org/support/plugin/facebook-for-woocommerce/unresolved/)
 * [Reviews](https://wordpress.org/support/plugin/facebook-for-woocommerce/reviews/)

 * 1 reply
 * 2 participants
 * Last reply from: [Rafy](https://wordpress.org/support/users/nawaz0705/)
 * Last activity: [3 years, 9 months ago](https://wordpress.org/support/topic/error-message-on-php-8-1/#post-15908356)
 * Status: resolved