As reported here and elsewhere , Yahoo has reduced the amount of free storage for Yahoo Mail users. The prior limit, 1 terabyte, is now reduced to 20 gigabytes. Users with a mailbox containing w…
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Here's a simple-but-cool tool created by Faisal Misle : smtp.codes . smtp.codes is a collection of SMTP response codes returned by email servers and a guide to help you unde…
Has this ever happened to you? Because it just happened to me! In theory, I should be on top of this sort of thing, because I've been writing scripts and code to generate ema…
Example SMTP Errors When sending email messages to the various AT&T consumer email domains (ameritech.net, att.net, bellsouth.net, currently.com, flash.net, nvbell.net, pacbe…
I've blogged about this before, covering the different types of NDRs (non-delivery reports, aka bounces or rejections) that you receive back when trying to send email messag…
Have you ever run into the SMTP bounce message "too old"? Perhaps with a status code of 602? Here's what that means! This isn't an SMTP rejection code enshrined…
Bounces (also called Non-Delivery Reports /NDRs or SMTP rejections) happen when you attempt to send email to a recipient and that attempt fails, typically because the recipient&#…
Time for another Tuesday Tip here on Spam Resource. Tuesday Tips are meant to be short little bits of wisdom, easily digestible deliverability knowledge nuggets. Today's to…
If you're trying to send email using an email server hosted on an IP address not expected to be running a mail server, your attempts to send mail to Gmail users is likely to…
My loss is your gain! I accidentally fumbled my DMARC record temporarily – locking everything down just a little too well for one of my domains – and then I sent an email to my t…
If you're trying to send email using an email server hosted on an IP address not expected to be running a mail server, your attempts to send mail to Gmail users is likely to…
Here's a tip that I think Salesforce Marketing Cloud users will find useful, especially in the context of the new Yahoo and Google sender requirements. Multi-bounce domain: …
Bounce message. SMTP rejection. Deferral message. Non-delivery report (NDR). 5xx error. 4xx error. No matter what you call them, there are a zillion different kinds of them out …
Gmail has very recently unveiled a series of new deferral/rejection messages. You may want to familiarize yourself with the following new SMTP responses: 421 4.7.28 Our system ha…
Sending mail to Microsoft domains can mean you get different types of bounces back for what is effectively the same problem. Check out these three different bounces, as an exampl…
Okay, so it should be obvious to everyone nowadays that email addresses die. They go dormant because the users on the other end of that mailbox have given up on that mailbox; hav…
Deliverability folks from a few different email sending platforms have mentioned seeing a new bounce from Comcast, in response when trying to mail certain comcast.net subscribers…
Are you seeing this bounce message when trying to send mail to Yahoo subscribers? 451 Message temporarily deferred due to unresolvable RFC.5321 from domain; see https://postmaste…
Google is saying that as early as December 2023, they're going to start retiring inactive accounts . Meaning, if you haven't signed into your Google account in at least t…
So you've seen a new bounce message and you're wondering how best to handle it. Where do you start? How do you troubleshoot it? I'd love to write a whole book on the …
