Blank Red Error When Placing Order

Hello,

I am using the latest WordPress and Woocommerce software on nginx web server.

We are using Xpress and XLink plugin built by ThemeHouse to make accounts on Xenforo and WordPress side same.

Everything was working without any problem, until last month. Right now, when some of our customer tries to place order, it gets a red blank error. Customer thinks that he/she can’t place order, so he/she tries again multiple times. But in reality all orders comes to your admin panel.

Because our WordPress and Xenforo connected together with Xpress and Xlink plugin, when error occurs in WordPress side, it throws that error to Xenforo logs.

First of all I checked if everyting is up to date. And yes, it is. Then I disabled every plugin and switched back to default WordPress theme. Problem solved. Then I enabled all plugins one by one and figured out that “Xpress” plugin causes that problem.

I wrote ticket to their support site but they said their code is not faulty, the problem is on WordPress+Woocommerce side.

So here is the error: (On error there are some sensitive information like our customers name, surname, e-mail address so i just erased them.)

Error: Call to undefined method Pelago\Emogrifier\HtmlProcessor\HtmlPruner::fromHtml() /var/www/html/wp-content/plugins/woocommerce/includes/emails/class-wc-email.php:570
From: Unkown account At 12 May 2020 13:55

#0 /var/www/html/wp-content/plugins/woocommerce/includes/emails/class-wc-email.php(649): WC_Email->style_inline()
#1 /var/www/html/wp-content/plugins/woocommerce/includes/emails/class-wc-email-new-order.php(98): WC_Email->send()
#2 /var/www/html/wp-includes/class-wp-hook.php(288): WC_Email_New_Order->trigger()
#3 /var/www/html/wp-includes/class-wp-hook.php(312): WP_Hook->apply_filters()
#4 /var/www/html/wp-includes/plugin.php(544): WP_Hook->do_action()
#5 /var/www/html/wp-content/plugins/woocommerce/includes/class-wc-emails.php(170): do_action_ref_array()
#6 /var/www/html/wp-includes/class-wp-hook.php(288): WC_Emails::send_transactional_email()
#7 /var/www/html/wp-includes/class-wp-hook.php(312): WP_Hook->apply_filters()
#8 /var/www/html/wp-includes/plugin.php(478): WP_Hook->do_action()
#9 /var/www/html/wp-content/plugins/woocommerce/includes/class-wc-order.php(372): do_action()
#10 /var/www/html/wp-content/plugins/woocommerce/includes/class-wc-order.php(221): WC_Order->status_transition()
#11 /var/www/html/wp-content/plugins/woocommerce/includes/class-wc-order.php(333): WC_Order->save()
#12 /var/www/html/wp-content/plugins/woocommerce/includes/gateways/bacs/class-wc-gateway-bacs.php(364): WC_Order->update_status()
#13 /var/www/html/wp-content/plugins/woocommerce/includes/class-wc-checkout.php(938): WC_Gateway_BACS->process_payment()
#14 /var/www/html/wp-content/plugins/woocommerce/includes/class-wc-checkout.php(1141): WC_Checkout->process_order_payment()
#15 /var/www/html/wp-content/plugins/woocommerce/includes/class-wc-ajax.php(464): WC_Checkout->process_checkout()
#16 /var/www/html/wp-includes/class-wp-hook.php(288): WC_AJAX::checkout()
#17 /var/www/html/wp-includes/class-wp-hook.php(312): WP_Hook->apply_filters()
#18 /var/www/html/wp-includes/plugin.php(478): WP_Hook->do_action()
#19 /var/www/html/wp-content/plugins/woocommerce/includes/class-wc-ajax.php(89): do_action()
#20 /var/www/html/wp-includes/class-wp-hook.php(288): WC_AJAX::do_wc_ajax()
#21 /var/www/html/wp-includes/class-wp-hook.php(312): WP_Hook->apply_filters()
#22 /var/www/html/wp-includes/plugin.php(478): WP_Hook->do_action()
#23 /var/www/html/wp-includes/template-loader.php(13): do_action()
#24 /var/www/html/wp-blog-header.php(19): require_once('/var/www/html/w...')
#25 /var/www/html/index.php(17): require('/var/www/html/w...')
#26 {main}

array(4) {
  ["url"] => string(18) "/?wc-ajax=checkout"
  ["referrer"] => string(26) "https://websiteurl.com/payment/"
  ["_GET"] => array(1) {
    ["wc-ajax"] => string(8) "checkout"
  }
  ["_POST"] => array(18) {
    ["billing_first_name"] => string(9) "CUSTOMERNAME"
    ["billing_last_name"] => string(6) "CUSTOMERSURNAME"
    ["billing_company"] => string(0) ""
    ["billing_country"] => string(2) "TR"
    ["billing_address_1"] => string(44) "CUSTOMER ADRESS"
    ["billing_address_2"] => string(13) "CUSTOMER ADRESS 2"
    ["billing_postcode"] => string(5) "POST CODE"
    ["billing_city"] => string(10) "PROVIDENCE"
    ["billing_state"] => string(4) "TR07"
    ["billing_phone"] => string(11) "CUSTOMER NUMBER"
    ["billing_email"] => string(22) "CUSTOMER MAIL"
    ["order_comments"] => string(0) ""
    ["shipping_method"] => array(1) {
      [0] => string(11) "flat_rate:2"
    }
    ["payment_method"] => string(4) "bacs"
    ["terms"] => string(2) "on"
    ["terms-field"] => string(1) "1"
    ["woocommerce-process-checkout-nonce"] => string(10) "b8b8f8aef3"
    ["_wp_http_referer"] => string(29) "/?wc-ajax=update_order_review"
  }
}