I have only received this twice now but wondering why it happens.
The transaction went through ok into Hikashop, put client through to Paypal for payment which they paid fine, but for some reason the amount that went to paypal was 1 cent more than what was recorded in Hikashop and when Paypal sent the details back to Hika, I get the error "Paypal payment notification refused:invalid amount" and hikashop records the order as cancelled.
I just changed order to shipped as I did receive the correct monies - I just edited one of the amounts in the order on Hika to match the paypal amount.
Would this happen as a result of rounding in Hika? Something to do with the Australia Post module, Fee for credit card charged?
Its not big deal as long as the client doesn't get a message saying the order has been cancelled.