Order Total invalid message with Paypal EC

[sbloomer]

I'm busy testing my new shop but getting an error thrown by ZenCart

An error occurred when we tried to contact the payment processor. Please try again, select an alternate payment method, or contact the store owner for assistance. (10401) 10401 Transaction refused because of an invalid argument. See additional error messages for details. - Order total is invalid.

Any pointers as to where I can start looking for the source of this error - the order totals are correct.

The checkout works with my other Payment Gateway

[sbloomer]

Ok I found my problem - my cart had USD removed as a currency, and Paypal needs it because it needs to convert from my country's native currency.