It does not give any errors. That was precisely the problem I encountered as I had been booking with an AWD code that would clearly say in the confirmation email that i would get the bonus miles but none of the miles would post to my airline account. I don't want to keep renting from Avis if my coupon will not be honored as I have already lost thousands of miles and would atleast get some other benefits from Hertz in the meantime until i am sure i will get the miles.