Hi

i am integrating uCommerce with Paypal

I have executed the steps mentioned in http://www.publicvoid.dk/SetupUCommerceToIncludePayPalAsAPaymentMethod.aspx

But during checkout process when i select Paypal and click submit, i get following error:

Order number series: "Default Payment Reference" does not exist.
System.String GetOrderNumber(System.String)
   at UCommerce.Transactions.CheckoutService.GetOrderNumber(String orderNumberName)
   at UCommerce.Transactions.Payments.ExternalPaymentMethodService.GetReferenceId(PaymentRequest paymentRequest)
   at UCommerce.Transactions.Payments.ExternalPaymentMethodService.CreatePayment(PaymentRequest request)
   at UCommerce.Transactions.Payments.ExternalPaymentMethodService.RequestPayment(PaymentRequest paymentRequest)
   at UCommerce.Xslt.TransactionLibrary.CreatePayment(Int32 paymentMethodId, Decimal amount, Boolean requestPayment, Boolean overwriteExisting)
   at UCommerce.Xslt.Library.<>c__DisplayClassb9.<CreatePayment>b__b8()
   at UCommerce.Xslt.Library.HandledCall[T](Func`1 method)

I am using umbraco v 4.7.2 and uCommerce v 2.6.1.0

Any help is appreciated

Thanks