I have installed the forums plugin on my woocommerce website. WP version 4.6.1 and Woocommerce 2.6.8. Now whenever some products are added to the cart instead of seeing the banner showing product was added to the cart a blank page is displayed. Odd part is it doesn't happen to all products. When I deactivate the forum plugin problem goes away.
I believe its only happening when a product utilizes the Woocommerce "Extra Product Options" plugin. http://www.themehigh.com/product/woocommerce-extra-product-options/
I'm rally sorry but we don't provide 3rd party plugin compatibility support yet. Our time is too limited, and we can't go through thousands of plugins.