Hi everyone, Hope you guys can help me.

I've searched the FAQ area but it does not work for me. I am unable to checkout using PayPal Website Payments Pro. It gives me an error:

10413 Transaction refused because of an invalid argument. See additional error messages for details. - The totals of the cart item amounts do not match order amounts.

However PayPal Express Checkout works fine for me.

I am using:
Zen Cart 1.3.8.
No add-ons
Tax: nil

Can anyone help me? Please. I've tried to edit some codes into the paypaldp.php but nothing happens.

Any help is greatly appreciated.