Blog – Word to the Wise

I’ve seen a bunch of folks panic about some phrasing in Google’s Email sender guidelines.
Buried deep in the Message formatting section Google say:
Don’t use HTML and CSS to hide content in your messages. Hiding content might cause messages to be marked as spam....

I wrote last year about using “stunt” nameservers for customer subdomain authentication – i.e. dynamically generating all the authentication records needed in DNS for each customer as needed.
For example, if you’re an ESP that has customers who can’t or won’t use their own domains and you still need to give them unique subdomains you can generate CNAME records to support white label DKIM authentication:...

We just got back from Amsterdam a couple of days ago, after attending the Deliverability Summit.
It may have been the best email event I’ve been to in several years. Not too big, not too small. Plenty of space and time to meet up with folks. Mostly great sessions, a better average than most conferences....

When trying to find out why Something Went Wrong during delivery of an email we sometimes want to look at the route by which it was delivered.
Did SPF break because of an unexpected forward? Did DKIM break because an intermediate mailserver modified the content of the message? Why did it take nine hours from the mail leaving our ESP to make it to the inbox? Did it really leave our ESP when...