Credit card declined with free app purchase

You must have a payment method set up in the iTunes store, even for free apps. In addition to being a way to pay, the payment method is a way of identifying you. And many free apps support in-app purchases, so you need to be prepared.

A “payment declined” message means that the issuer of the credit or debit card you have on file in your iTunes account rejected a charge or account confirmation. It is not an Apple problem; Apple is just passing through the message from your issuer. There are a number of reasons the charge or verification might be declined:

1. Insufficient balance or account in arrears
2. Account suspended for suspected fraud (not necessarily by you)
3. Error in card number
4. Wrong expiration date
5. Wrong security (CCV) code
6. Address in your iTunes account does not match exactly the billing address for the card
7. The card was not issued in the country of the iTunes store

Even for free apps, you account has to be verified. Apple does this with a valid credit card. Once you add a valid card, you can remove it and download free apps.