Hey, that worked! Thanks, Edward, I never would have thought to try that.
One other question: I’m trying to change the “Add to Cart” button on the product pages to a custom image. When I go to Settings > WP Shopping Cart and scroll down, there is an option that says “Add to Cart button text or image,” where the instructions say “To use a customized image as the button simply enter the URL of the image file. e.g. https://www.your-domain.com/wp-content/plugins/wordpress-paypal-shopping-cart/images/buy_now_button.png.”
But when I upload an image and paste its url into this box, the Add to Cart button is not updating on my product pages. Any idea how this is supposed to work?