It started last week when I was trying to sign up for Ron Paul Christmas. For some peculiar reason, I didn’t receive the welcome email. After talking with the site owner, it turned out (mt) was rejecting the email because the email address didn’t exist on the sending server.

Now, this isn’t particularly unusual. There is no requirement1 that an email address actually exist for a server to send email as if it were from that address. This is especially true from Wordpress blogs, which often send email from accounts on behalf of their owners. Now, since this is only used for outgoing email, in most cases users would never bother setting the email account up. Why would you? You’re never going to be receiving email there2, so what’s the point?

Well, (mt) apparently knows better than you do… For “security reasons”3, their grid service does a “callback” check on every incoming email address. If the server handling mail for doesn’t recognize that account (such as our example), (mt)’s server will reject the message.

I’ve tried to point out that this kind of behavior can be detrimental, particularly in the age of blogging and web services we now exist in, but the best answer I’ve been able to get out of (mt) is that I should add the sending address to their Mail Protect whitelist. Well great, unless I can add *@* to the whitelist, or at the very least wordpress@*, that’s hardly a viable solution - how do I know the address that’s sending to me if I never get the email?

If you use Media Temple’s grid service4, please contact (mt) immediately and tell them this is an unacceptable situation. I love a lot of aspects of their grid service, but this is clearly not one of them…

  1. In most cases, anyway. 
  2. Except for bounces, should someone put in an invalid email address 
  3. According to the support representative that responded to my ticket. 
  4. Or you want people who do use it to actually receive emails you send to them. 
Originally published and updated .