Why did I get API error code 10746?

PayPal returned API error code 10746 -  This transaction cannot be processed. Please use a valid country on the billing address.

The country code passed in with the billing address is not a PayPal-supported country.

For a list of PayPal-supported countries, visit our complete PayPal Supported Countries listing.

See the Developer Portal for a complete list of NVP/SOAP API error codes.