Have you had a 10413 error in your PrestaShop site while taking a Paypal transaction? If so the solution is easy to fix it. The reason for the error code is that coupons and taxes are handled incorrectly in some versions of PrestaShop. So you have to delete the variable being sent to Paypal that tells Paypal how many items are being sent across. 

You can view this forum post on the PrestaShop forums for information on how to fix the issue. 

If you need adivce or support with your PrestaShop site feel free to contact us and we will do our best to help you out.