Test credit card numbers for use with PayPal sandbox

Question

I\'m having trouble testing credit card payments with PayPal\'s sandbox. When viewing a buyer\'s sandbox account\'s profile from within developer.paypal.com, I can see the f

Answer 1

It turns out, after messing around with all of the settings in the test business account, that one (or more) of the fraud related settings in the payment receiving preferences / security settings screens were causing the test payments to fail (without any useful error).