I'm running a web-based store where order confirmations are sometimes blocked and don't reach the intended user. The structure of the business model is such that our product is marketed to the end-user by a 3rd parities - affiliates how are known entities to the end-users and email is freely exchanged between end-users and our affiliates.

Our confirmations being blocked is becoming a big enough problem that we are considering implementing a system where a 'confirmations' address is created within the affiliates domain, then we'd have our app send via the affiliate's mail server instead of our own. But that'd be lots of work.

The idea has been raised to have our app use our affiliates' email in the FROM field but still send from our server. My thinking is that would be detected at the end-users side and blocked just as often - we dealing with institutions large enough at least some checks up at the perimeter.

Is this assumption correct (more likely to be blocked) or is there a less round about way to send messages under the auspices of 3rd parties?

thx