Yesterday I learned that some ESPs don’t support the reply to: address. I asked around to discover which ESPs did. Here’s what I learned. ESPs that support reply-to: ActiveCampaignAmazonSESConstantContactCampaign MonitorCordialDelivraDoListEloquaEmmaEpsilonGetResponseHubSpotiContactListrakMailkitMailUpMarketoN6PardotwordResponsysSailthruSFMCSharpspringTwilio / SendGridZeta Global...
The perfect email
More and more I’m moving away from consulting on technical setup issues as the solution to delivery problems. Delivery is not about the technical perfection of a message. Spammers get the technical right all the time. No, instead, delivery is about sending messages the user wants. While looking for something on the blog I found an old post from 2011 that’s still relevant today. In...
May 2016: The Month in Email
Summer, already? Happy June! Here’s a look at our busy month of May. I had a wonderful time in Atlanta at the Salesforce Connections 2016 conference, where I spoke on a panel about deliverability. While in Atlanta, I also visited our friends at Mailchimp, and later spoke at the Email Innovations conference in Las Vegas, where I did my best to avoid “explaining all the things”. Since my speaking...
Pete and Repeat
Pete and Repeat were on a boat. Pete fell out, who was left?
I was searching the blog for some resources today and these were the first two posts that showed up on the search results. I often feel like I’m repeating myself, but sometimes I am.
Check your tech
One of the things we do for just about every new client coming into WttW is have them send us an email from their bulk mail system. We then check it for technical correctness. This includes things like reviewing all the different From headers, rDNS of the connecting IP, List-Unsubscribe headers and authentication. This is always useful, IMO, because we often find things that were right when they...
PTR Records
PTR records are easy to over look and they have a significant impact on your ability to deliver mail without them. Some ISP and mailbox providers will reject mail from IP addresses that do not have a PTR record created. PTR records are a type of DNS record that resolves an IP address to a fully qualified domain name or FQDN. The PTR records are also called Reverse DNS records. If you are...
AHBL Wildcards the Internet
AHBL (Abusive Host Blocking List) is a DNSBL (Domain Name Service Blacklist) that has been available since 2003 and is used by administrators to crowd-source spam sources, open proxies, and open relays. By collecting the data into a single list, an email system can check this blacklist to determine if a message should be accepted or rejected. AHBL is managed by The Summit Open Source Development...
M3AAWG Recommends TLS
SSL or Secure Sockets Layer is protocol designed to provide a secure way of transmitting information between computer systems. Originally created by Netscape and released publicly as SSLv2 in 1995 and updated to SSLv3 in 1996. TLS or Transport Layer Security was created in 1999 as a replacement for SSLv3. TLS and SSL are most commonly used to create a secure (encrypted) connection between your...
The anatomy of From:
Compared with some of the more complex pieces of the email protocol the From: header seems deceptively simple. But I’ve heard several people be confused about what it’s made up of over the past couple of months, so I thought I’d dig a bit deeper into how it’s defined and how it’s used in practice. Here’s a simple example: There are two interesting...
Horses, not zebras
I was first introduced to the maxim “When you hear hoofbeats, think horses not zebras” when I worked in my first molecular biology lab 20-some-odd years ago. I’m no longer a gene jockey, but I still find myself applying this to troubleshooting delivery problems for clients. It’s not that I think all delivery problems are caused by “horses”, or that...