Magento sends too many confirmation emails

I have a Magento store that apparently sends too many confirmations emails on an order. My theory is that the emails are resent all over again to the store admin when the customer tries to shop e开发者_如何学JAVAntering an inexistent email address.

How can I debug and/or fix this?

Thanks

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Is the customer's email getting returned to sender? If so try setting the sender address to a blackhole, a mailbox that drops all messages. It's not uncommon for sites to have a "noreply@" address for this purpose.