FIXED: Critical Error caused by WooCommerce Delivery Slots by Iconic

My guys at Grillo Services are the best. Clients for 15 years now or so and when something happens to them I respond as fast as possible. In this case I got a server side note from WP Engine that there was a critical error as seen below. This is why WP Engine is the best.


[Grillo Services] Your Site is Experiencing a Technical Issue

WordPress has a built-in feature that detects when a plugin or theme causes a fatal error on your site, and notifies you with this automated email.

In this case, WordPress caught an error with one of your plugins, WooCommerce Delivery Slots by Iconic.

First, visit your website

and check for any visible issues. Next, visit the page where the error was caught — and check for any visible issues.

Please contact your host for assistance with investigating this issue further.

If your site appears broken and you can’t access your dashboard normally, WordPress now has a special “recovery mode”. This lets you safely login to your dashboard and investigate further.

When seeking help with this issue, you may be asked for some of the following information:
WordPress version 6.5.3
Active theme: Pro Child Theme (version 1.0.0)
Current plugin: WooCommerce Delivery Slots by Iconic (version 2.1.0)
PHP version 8.2.19


Literally out of nowhere the delivery slots plugin blew up. A lot of site owners don’t want to believe a site can just go down but the way I explain it is it’s just like a house or a car. There’s a lot of moving parts and things just break sometimes.

So, the troubleshooting begins. Why, what is the conflict? Did an auto update, Woo update, WP version update cause it? Did we get hacked or compromised?

Well after a bunch of trial and error I interfaced with the developer and they provided the fix in the form in a plugin update (2.2.0).

I will report back when/if they tell me what this was but all is working again:

This was the error:

PHP Fatal error: Uncaught Error: Class “WooCommerce\Shipping\Table_Rate\Helpers” not found in /nas/content/live/grilloservices/wp-content/plugins/iconic-woo-delivery-slots/inc/class-compat-table-rate-shipping.php:76\nStack trace:\n#0 /nas/content/live/grilloservices/wp-content/plugins/iconic-woo-delivery-slots/inc/class-compat-table-rate-shipping.php(49): Iconic_WDS_Compat_Table_Rate_Shipping::get_shipping_rates(Object(WC_Shipping_Table_Rate))\n#1 /nas/content/live/grilloservices/wp-includes/class-wp-hook.php(324): Iconic_WDS_Compat_Table_Rate_Shipping::shipping_method_options(Array, Object(WC_Shipping_Table_Rate), Object(WC_Shipping_Zone))\n#2 /nas/content/live/grilloservices/wp-includes/plugin.php(205): WP_Hook->apply_filters(Array, Array)\n#3 /nas/content/live/grilloservices/wp-content/plugins/iconic-woo-delivery-slots/iconic-woo-delivery-slots.php(1662): apply_filters(‘iconic_wds_zone…’, Array, Object(WC_Shipping_Table_Rate), Object(WC_Shipping_Zone))\n#4 /nas/content/live/grilloservices/wp-content/plugins/iconic-woo-delivery-slots/inc/admin/settings.php(815): Iconic_WDS->get_shipping_method_options()\n#5 /nas/content/live/grilloservices/wp-includes/class-wp-hook.php(324): jckwds_settings(Array)\n#6 /nas/content/live/grilloservices/wp-includes/plugin.php(205): WP_Hook->apply_filters(Array, Array)\n#7 /nas/content/live/grilloservices/wp-content/plugins/iconic-woo-delivery-slots/inc/vendor/wp-settings-framework/wp-settings-framework.php(151): apply_filters(‘wpsf_register_s…’, Array)\n#8 /nas/content/live/grilloservices/wp-content/plugins/iconic-woo-delivery-slots/inc/vendor/wp-settings-framework/wp-settings-framework.php(113): Iconic_WDS_Settings_Framework->construct_settings()\n#9 /nas/content/live/grilloservices/wp-content/plugins/iconic-woo-delivery-slots/inc/class-core-settings.php(106): Iconic_WDS_Settings_Framework->__construct(‘/nas/content/li…’, ‘jckwds’)\n#10 /nas/content/live/grilloservices/wp-includes/class-wp-hook.php(324): Iconic_WDS_Core_Settings::init(‘’)\n#11 /nas/content/live/grilloservices/wp-includes/class-wp-hook.php(348): WP_Hook->apply_filters(NULL, Array)\n#12 /nas/content/live/grilloservices/wp-includes/plugin.php(517): WP_Hook->do_action(Array)\n#13 /nas/content/live/grilloservices/wp-settings.php(695): do_action(‘init’)\n#14 /nas/content/live/grilloservices/wp-config.php(121): require_once(‘/nas/content/li…’)\n#15 /nas/content/live/grilloservices/wp-load.php(50): require_once(‘/nas/content/li…’)\n#16 /nas/content/live/grilloservices/wp-cron.php(46): require_once(‘/nas/content/li…’)\n#17 {main}\n thrown in /nas/content/live/grilloservices/wp-content/plugins/iconic-woo-delivery-slots/inc/class-compat-table-rate-shipping.php on line 76’

From Iconic support:

Hey Michael,

Thanks for your patience.

I have read your query and would like to mention that there was a compatibility issue between WooCommerce Delivery Slots and Table Rate Shipping for WooCommerce plugins and that caused the problem.

Since it has been fixed in the latest update, you will not face this issue again.

Please don’t hesitate to ask if you have any other queries.


Their support is quite good for anyone scouting out their plugins. This is a wrap.