Thanks. Yes, under SEO & URLS, the Order Confirmation has a friendly URL, and PayPal module does not have any page for Order confirmation without a friendly URL. Under SEO & URL, Order Confirmation is going to a default Prestashop page, order-confirmation.

After payment is completed in PayPal, when clicking the link to return to the site, I get to the site, but a 404 page not available for the order confirmation. Here is what the link shows: [mysite]/order-confirmation.php?id_cart=20&id_module=73&key=[key]

Shopping cart ID is correct for the purchase. Under SEO & URL, Order Confirmation is going to a default Prestashop page, order-confirmation.