I am using v2.015, and paypal express checkout. i ran few test transactions, and i am having a big problem. it shows that transaction fails even thou, payment goes through.
In payments/certificates change api_certificate.pem.txt to cert_key_pem.txt and see if that helps.
Thanks for the response, but i remember that i played with the order status a while back (since my site still is in test mode), that caused the problem. now fixed. thanks for your response thou!