After PayPal payment, the following message is received by the AShop administrator.
Suspected payment manipulation: customer@emailaddress.com, firstname, lastname, productid, inv#, IP address
The money was recieved thru paypal, but the order is not recorded within AShop and the receipt is not sent to the customer.
This message is sent when PayPals IPN verification reports the payment as invalid. This should only occur if the payment for some reason haven't been transfered by PayPal, for instance if a customer tries to send the form fields manually to cheat the order.php script in AShop, but it seems that there is some kind of bug in PayPals IPN system that could cause this to happen in some other situations too.
We think that it might have had something to do with the fact that the customer signed up for a PayPal account at the same time that he ordered something from the site, but we are not sure. We guess is that this is caused by PayPal, not by Ashop.
If this occurs with your AShop installation, try a test transaction. You can't send money to yourself, so you will need another PayPal account to test with. PayPal allows two accounts per person; a business account and a personal account. You can easily create an unverified personal account for testing at PayPal.com.