headers
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 they say it did? Did Microsoft internal handoffs break something again? Received headers are the breadcrumbs that record the path an email took. Every time a mailserver receives an email it adds a Received header at the top of the mail (so the most recent Received headers come first). And it mustn’t modify any of the existing Received headers. A Received header looks complex, but they have quite a strict structure, and they’re fairly easy to read
Steve Atkins from Word to the Wise just released a very cool new tool called Aboutmy.Email. Bookmark it now! What do you do with it? Go to the Aboutmy.Email website, copy the unique email address it hands you, and launch your newsletter or campaign to that address. What happens next? Aboutmy.Email gives you a detailed report, checking your domains, headers, content and more to look for problems. It even has a “Good Practice” review section, which is code for “Does your email seem to comply with the new Yahoo and Gmail sender requirements?” Want to see an example report? Here’s one for a Spam Resource newsletter. What are all the checks it does? Steve says that it reviews: SPF, DKIM, DMARC BIMI, including details about the certificate and image What IP address it was sent from, and whether it has valid DNS The size of the mail as sent (no
A few days ago, Google started notifying (some) Google Workspace customers of updated spam filter/blocking changes coming to the Gmail email service. They’re moving to more proactively block emails that have headers violating RFC 5322, and it is believed that this is an attempt to help prevent DKIM replay attacks. Read on to learn more about what this means and how it could impact email senders.In the notification below, they indicate that they’ve sent this only to Workspace users they think may be impacted by this change, but truth be told, it affects the entire internet, as it could impact anyone sending email messages to any user at a Google-hosted mailbox.The notification: We’re writing to let you know about an upcoming change to your Gmail services. Gmail will start rejecting messages that are non-compliant with Internet Message Format standards and contain more than one single-instance email header as of April
DELIVTERMS: The weekly series here on Spam Resource that defines deliverability terminology. Today, I’m going to talk about the Friendly From.What is the friendly from? It’s not quite its own separate header, but it is a field in your from header. It is the text that goes next to your email address in the from header.If the from address header in my email looks like this:From: Al Iverson That means that the from address is aiversontestmail@wombatmail.com and the “friendly from” is “Al Iverson.”Some systems enclose the friendly from in quotes, like this:From: “Al Iverson, not a lawyer” This helps prevent formatting glitches in some cases, like if you include a comma in your friendly from. In that case, if you don’t put the whole thing in quotes, there’s a good chance recipients could end up with a very funky looking from address, depending on how their mail application or webmail…
(Here’s an updated version of a post from way back in 2018, with additional resources! I hope you find it handy.)Need a tool to parse message headers? Trying to break down how long it took to hand off an email message between servers? Want to check for blocklistings, content scoring or link issues? Here’s a few different tools that do a few different things.First, let’s check message headers using this tool from Google, or this (I think unofficial) version for Microsoft headers. Both do basically the same thing — you paste in the email headers and it will parse them, giving you a breakdown of how much time it took between each server hop. Very handy for troubleshooting delivery delays. Did a Gmail server hold on to your message for four hours before passing it on? Or did it never leave your ESP’s mail server? That’s what tools like these…