Minimize the chance my email is blocked/filtered as spam

Question

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

Answer 1

You can "spoof" their email domain: just make sure they have your mail server's in their SPF records. I do this all the time for clients (on a smaller scale, but I'm sending out hundreds of confirmation e-mails, forum notifications, etc. every day from dozens of different domains; haven't had a problem yet).

Also make sure you have the items mentioned by pQd in place.

Answer 2

1. send valid messages - with nice / full headers, proper plain-text part and probably rich-text.

2. analyze what are the reasons for blocking - if someone uses spamassassin - check which rules were triggered by your mails.

3. ensure you send mails from server that is not on any blacklist - check it here or here or at other places. if you are blacklisted - find out why and 'drag' your ip out of blacklists.

4. configure properly rev-dns for your smtp server so it points to existing domain.

5. make sure you send mails with sender address and return address @valid.domain.com. add spf record to it that permits your smtp to send legitimate messages.

6. add your self to some white-lists like http://www.dnswl.org/

Answer 3

From our fearless leader here. Most applies to regular email as well as code.

Answer 4

Here is a link from Jeff Atwood (Stack Overflow)

http://www.codinghorror.com/blog/2010/04/so-youd-like-to-send-some-email-through-code.html