Fatal error: Uncaught Error: Undefined constant "WC_VERSION" in /home/www/berggreen.eu/wp-content/plugins/woocommerce-pay-for-payment/inc/class-pay4pay.php:40 Stack trace: #0 /home/www/berggreen.eu/wp-content/plugins/woocommerce-pay-for-payment/inc/class-pay4pay.php(16): Pay4Pay->__construct() #1 /home/www/berggreen.eu/wp-content/plugins/woocommerce-pay-for-payment/woocommerce-payforpayment.php(32): Pay4Pay::instance() #2 /home/www/berggreen.eu/wp-includes/class-wp-hook.php(324): pay4payment_plugin_init('') #3 /home/www/berggreen.eu/wp-includes/class-wp-hook.php(348): WP_Hook->apply_filters(NULL, Array) #4 /home/www/berggreen.eu/wp-includes/plugin.php(517): WP_Hook->do_action(Array) #5 /home/www/berggreen.eu/wp-settings.php(578): do_action('plugins_loaded') #6 /home/www/berggreen.eu/wp-config.php(95): require_once('/home/www/bergg...') #7 /home/www/berggreen.eu/wp-load.php(50): require_once('/home/www/bergg...') #8 /home/www/berggreen.eu/wp-blog-header.php(13): require_once('/home/www/bergg...') #9 /home/www/berggreen.eu/index.php(17): require('/home/www/bergg...') #10 {main} thrown in /home/www/berggreen.eu/wp-content/plugins/woocommerce-pay-for-payment/inc/class-pay4pay.php on line 40