I’m getting an internal server error on the checkout page. I followed the thread that was archived on this recently and unchecked the enable AJAX add to cart buttons on archives. I’m still getting the error. Orders are showing up in woocommerce but after place order button is clicked, it just scrolls to the top of the page and shows internal server error. https://www.lebonsweets.com X is up to date, woocommerce is up to date. This just recently happened after update to WordPress 4.6
You could try testing for a plugin conflict. You can do this by deactivating all third party plugins, and seeing if the problem remains. If it’s fixed, you’ll know a plugin caused the problem, and you can narrow down which one by reactivating them one at a time.