I have been trying for the last 2 days to purchase a license for the Enthuware mock exams online by a credit card. Each time I submit the order, I get an error message that says, "order not accepted". I am really puzzled. It is a valid credit card which I use on a regular basis. In fact, it is the same credit card I used for buying Mala Gupta's book on Java certification. I have sent a message to Enthuware but I am yet to receive a reply.