I have some problem with PayPal which appeared in the last 2 weeks, but it does not occur for every payment I receive in PayPal for Magento orders.
At System --> Configuration --> PayPal, field “Email Associated with PayPal Merchant Account” I have configured an email address registered with my PayPal account, which is not my primary email address for PayPal. However, there are some payments for Magento orders for which the field “Payment Sent to” is set to my primary email address registered with PayPal. My primary email address is totally unknown for my Magento Store; I mean that I haven’t configured that email address anywhere in my store configuration. So, I presume that for some reason PayPal puts on its own that email address.
The above problem impacts the IPN I receive from PayPal. Namely, PayPal sends the IPN to my Magento store, but for the payments whose the field “Payment Sent to” is set to my primary email address registered with PayPal, Magento discards the IPN with the following error:
[exception] => Requested email@example.com and configured firstname.lastname@example.org merchant emails do not match.
As a result, these orders are shown as unpaid in my Store, while the customer has paid for them, of course.