When attempting to make a donation I get an error saying
"The supplied currency code is either invalid, not supported, not allowed for this merchant or doesn't have an exchange rate."
When I spoke to authorize.net, they said it appears NationBuilder was set up as USD instead of CAD which causes the error. I am set up to accept CAD in my authorize.net account as well as in my nation settings under Settings > Defaults > Basics > Currency.
After troubleshooting with several customers, this error appears when the payment processor and merchant account currency codes do not align with the same currency. Customers have fixed this issue by either recreating either their Authorize account or merchant account to align with the same currency. That currency must also be reflected in NationBuilder.
1) Payment processor = CAD
2) Merchant account = CAD
3) NationBuilder currency settings = CAD