I received a payment via Paypal and then received an email saying that "The transaction was not completed successfully. eShop could not validate the order. Please double check all settings in eShop and at paypal to confirm they are both correct."
I've checked http://quirm.net/wiki/eshop/setting-up-merchant-gateways/paypal/ and all my info is correct. My emails, location, tax, etc settings are all correct.
What's making the transaction fail? And are my customers receiving an email saying it failed? The money is in Paypal, so can they be assured the sale went through or should I email them to confirm I have their money/will send the product?