comcast
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:550 5.2.0 – Account Closed, Please RemoveWhat does it mean? Nobody home! That’s a dead account. The user is an ex-parrot. Send them no more mail. Seems simple enough to me, but people always have questions about this kind of thing, so I figured I’d share it with you all.And of course, there’s still this usual bounce:550 5.1.1 – Not our CustomerMeaning that’s not a valid Comcast subscriber address, either. Same deal, nobody home. It likely means nobody was ever home at that address, but even if I’m slightly wrong about that, the net here is the same; time to stop mailing that address.And then there’s also a slightly rarer 4xx bounce that looks like this:450 4.2.0 – Recipient temporarily unavailableThose ones, you should retry per
Twilio Sendgrid’s Denis O’Sullivan recently put together this great Q&A With Alex Brotman from Comcast, and it provides stellar insight for senders. No secret sauce will be leaked here today, but there’s great knowledge here to help people sending emails understand what’s going on and what to do to prevent and/or handle various problems. Thanks to Alex, and thanks to Denis!
Here’s an ever perplexing question (and one that results in a lot of traffic to my blog): Do Comcast email addresses end in .com or .net? Is it comcast.com or comcast.net? Am I aliversonchicago@comcast.com or aliversonchicago@comcast.net?Comcast has live email addresses at both comcast.com and comcast.net. The difference is, comcast.net email addresses are reserved for customers of Comcast/Xfinity, while comcast.com addresses are reserved for employees of Comcast.A while ago I posted a full breakdown of Comcast domains, but I thought it would be good to call this out more explicitly today — regular joe users signing up for your emails using the email address that comes free with their Comcast Xfinity cable service? That’s always going to be comcast.net.Some platforms will even block signups from emails at comcast.com, because most of those signups are typos — people who typed comcast.com when they should have typed comcast.net if they wanted to give
It’s time for another BIMI update, and this time it’s chock full of new details that you’ll want to know! So let’s get right to it.The Authindicators Working Group (the folks behind the BIMI spec) have just indicated that Apple plans BIMI support! The information published so far suggests that it’s coming this fall to both iOS and MacOS. Beyond that, details are light; so don’t ask me (or them) for greater definition just yet. I’m sure when they have details, they will share. And when they share, I will share.Where does that leave us today? Here’s your status update on ISP support for BIMI as of June, 2022.Yes: Which ISPs/MBPs/email applications support BIMI today or plan to support it in the near future: Apple (iOS and MacOS email clients), Fastmail, Gmail, and Yahoo Mail. (This also includes Pobox, AOL/Netscape, and Google for Business)Perhaps: Which ISPs are currently considering BIMI support:
It’s time for your periodic BIMI adoption status update. A quick overview of what this is all about: BIMI is a standard being adopted by multiple internet services providers (ISPs) to allow the display of a sender’s logo along side email messages, when displayed on a mobile device or in a webmail client. Some ISPs and mail clients have had a sender logo display function for a while now (one example is Gravatar), but BIMI is an attempt to standardize and regulate this mechanism across the email ecosystem.Adoption by senders seems a bit slow; but the spec only went public in 2019, which isn’t that long ago. Also, it suffers a bit from the “chicken and egg” problem — it’s hard to convince senders to adopt the standard if receivers haven’t adopted support for the standard. But now with two of the top three B2C mailbox providers (Yahoo and Gmail) having BIMI support, I’m…
Hey! I know that people find the ISP domain guides useful, so I thought I’d fire up the blog machine to share info about our friends at American telecommunications company Comcast (Xfinity) and their various email domains. I’m not sure that everybody knows this information already, so I though it would be good to share.It’s mostly pretty simple, and it boils down to this:comcast.net: People who have cable internet service from Comcast (aka Xfinity) and who use Comcast’s email service are going to have their mailboxes in this domain name.comcast.com: Comcast employees are going to have their mailboxes in this domain.cable.comcast.com: Comcast employees will be found here, too.xfinity.com: does have an MX record and you might think it’s alive for email, but I’m not seeing any widespread evidence that any significant number of mailboxes are hosted here.If you run some sort of website where people signup for email messages from…
American multinational telecommunications conglomerate Comcast, most well-known to us Internet users here in the US as the provider of cable modem-based internet service Xfinity, has announced that they’ll be sending outbound mail from subscribers via new (additional) IP addresses ranges.On the Mailop list, a representative from Comcast shared that the new IP ranges are as follows:ip4:96.103.146.48/28 ip4:96.102.19.32/28 ip4:96.102.200.0/28ip6:2001:558:fd01:2bb4::/64 ip6:2001:558:fd00:56::/64 ip6:2001:558:fd02:2446::/64These are indeed included in the comcast.net SPF record.
It’s been a while since I’ve posted a BIMI status update, and things are changing! Things are standardizing! Things are getting good. So, let’s get right to it…