Email Blogs

Lumen Technologies, aka CenturyLink, absorbed Embarq, combined with Qwest, which acquired USWest (if you’ve really been around a while) and is a telecommunications provider come together from many parts, with bits of them descended all the way from Mountain Bell, Pacific Northwest Bell and Northwestern Bell, the latter being the predecessor company that ran the copper wires that eventually delivered DSL internet service to my Minneapolis apartment starting near the turn of the millennium. Fast forward to today, and they continue to provide consumer internet access in various locales across the USA, and that includes hosting consumer email services for those users across a number of domains. Those domains include:digisys.netcswnet.commebtel.netcenturylink.netq.comembarqmail.comgrics.netcenturytel.netqwest.netcoastalnow.netgulftel.comThe MX for these domains points at mx.centurylink.net, but if you connect on port 25 and read the SMTP banner, you’ll see “cloudfilter.net” which is actually Cloudmark. Thus, if you’re having spam-related deliverability troubles at CenturyLink, you’ve probably got a Cloudmark

Apple’s latest computer operating system, macOS Sonoma, launches today, September 26th. With that launch comes a loss of email-related functionality. The Apple Mail app in Sonoma no longer has support for legacy mail plug-ins. Plug-ins included tools like Mailbutler, SpamSieve and EagleFiler (and others). Apparently a new MailKit-based framework now exists for Apple Mail plugins, but is said to be more limited than what was previously available. Tobias from tool-developer Mailbutler explains more of what’s changed here.I don’t really know enough about these various plug-ins to have specific opinions on them, but in general, mail plugins that have access to email data always make me a bit nervous from a privacy perspective. Apple’s privacy-first focus makes me wonder if they these mail plug-ins potentially had access to more data than Apple was comfortable with.

I realize that talking about ISP feedback loops can just lead to a lot of blank stares from folks. Not because they’re stupid, by any means. But because for the most part, FBLs are such a basic, foundational part of an email sending platform, and most of those platforms long ago “just dealt with it” — meaning dealt with the set up and management of feedback loops many years ago (almost 20 years, in some cases), that a lot of marketers haven’t ever been required to set up or manage feedback loops themselves. Indeed, some modern email sending or relay platforms just manage the feedback loop stuff for you, automatically, suppressing complainers and generating reporting. So some newer platform maintainers may not have ever even set up and managed ISP feedback loops.Question number one: If nobody really knows about or remembers this, and if new platforms perhaps don’t even bother

One assumes the rendering tools like Email on Acid and Litmus have already been updated with this new desktop client, the Outlook for Windows email app that just launched, since it has been available in a public preview since May 2022.If you’re a Windows user, you’re longing for a desktop email client, and you want a new email client, Microsoft’s got you covered. Reports say that this new Outlook for Windows application will eventually replace the built-in Windows Mail and Calendar app. But if you’re curious and want to try it now, just after its official release, click on through.Read more here.

As noted recently, Validity plans to start charging for ISP feedback loop complaint feeds. Free users will get some sort of aggregate dashboard that is perhaps similar to what one sees in Google Postmaster Tools, but it sounds as though there will be no individual complaints fed, and no opportunity to log or unsubscribe complaints or complainers.If some number of sending platforms decide not to pay this fee, and thus stop receiving spam complaint feeds, this is likely to have an impact on the email ecosystem. How much of an impact? To understand that, we should start by identifying the potential beneficiaries of ISP feedback loop complaints:The end user. In most cases, a “report spam” complaint results in that end subscriber getting unsubscribed from a particular sender. The mail stops. Now, the mail will not stop, perhaps allowing the user to report spam again and again, possibly causing more negative

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 example:Your message to nobodyhome@kickbox857.onmicrosoft.com couldn’t be delivered.firstname.lastname wasn’t found at company.com.550 5.1.10 RESOLVER.ADR.RecipientNotFound; Recipient firstname.lastname@company.com not found by SMTP address lookup550 5.5.0 Requested action not taken: mailbox unavailable (S2017062302). [HE1EUR01FT020.eop-EUR01.prod.protection.outlook.com 2023-09-19T15:05:34.324Z 08DBB71928CA8F8E]: host company-com.mail.protection.outlook.com[52.101.40.6] said: 550 5.4.1 Recipient address rejected: Access denied. [CY4PEPF0000EE3C.namprd03.prod.outlook.com 2023-09-18T12:48:32.808Z 08DBB45899852BA7] (in reply to RCPT TO command)All of these are essentially “user unknown” or “invalid user” bounces, returned from attempting to send mail to an invalid or closed address at a Microsoft-hosted email domain.The first one is the more “plain english” version that Microsoft builds into the DSN (Delivery Status Notification) that O365 will send back in some cases.The second one? Seems self explanatory. O365 again, very clearly saying “recipient not found.”The third one? This is your

Onet is Poland’s number two mailbox provider (behind Wirtualna Polska). Onet’s domains subscriber email domains include op.pl, onet.pl, vp.pl, poczta.onet.pl, autograf.pl, buziaczek.pl, onet.com.pl and amorki.pl.And with all this talk of subscriber inactivity policies (starting with Gmail’s recent announcements) I’ve been looking to catalog account inactivity details whenever possible. And Onet just sent me an email letting me know about the policy (and that my test account is long dormant):Due to the lack of logging in to your onet.pl e-mail account for a period exceeding 12 months, we would like to inform you that in accordance with the provisions of the Onet Poczta Service Regulations (point 7.3 letter i), your account and all its contents in 30 days it will be permanently deleted (without the possibility of recovery), which will affect all services associated with it.If you want to keep this account, all you need to do is log in to

Gmail has long pushed for adoption of email authentication best practices from email senders, effectively making it tough to get to the inbox without proper email authentication in place. They also, for years now, have been very cautious about what mail they accept over IPv6, declining to accept mail over IPv6 that fails authentication checks. Well, now those same checks now apply to all mail sent to Gmail — over IPv4 or IPv6. Meaning, if you want to send mail to Gmail, you need to authenticate that mail with Domain Keys Identified Mail (DKIM) or Sender Policy Framework (SPF).If you’re trying to send mail to Gmail subscribers, and the mail doesn’t authenticate properly, it’ll be rejected with this error message:550-5.7.26 This mail is unauthenticated, which poses a security risk to the sender and Gmail users, and has been blocked. The sender must authenticate with at least one of SPF or

Spamhaus just announced that they’ve “reinvigorated” the ASN-DROP list, now available in JSON format. The point of this whole thing is for network operators (think ISPs and similar) to just totally block off any potential connections with really bad networks that are spewing nothing but spam, phish and other garbage.In theory this should not impact your typical marketing sender, but it’s good all of us to be aware of what this is. They’re blocking, in some cases, some bad guys who would happily take threats to a phyiscal level with Spamhaus people, given the chance. If the bad guys can’t route their bad stuff, they can’t rip people off, and they don’t make as much (ill gotten) money. That’s why Spamhaus folks are sometimes cagey about full names and locations, in case you’re wondering — not because they’re worried about how a Fortune 500 retailer might react to an SBL

For those that don’t know, I was director of deliverability for Salesforce Marketing Cloud (previously ExactTarget) from 2006 through 2021. My love of all this email and guiding clients toward deliverability success even predates that — having started my first email sends (and building my first email filters) way back in the late 1990s. But it was during the Salesforce days where I was most able to “spread the word” of deliverability best practices. I’m insanely proud of the client interactions and knowledge share I was able to do while I was there. It pleases me that you can still find remnants of those days online!For example, here’s a link to a recorded session I did for Salesforce’s Trailhead Live in 2019. That’s a few years ago now, but I think this is still a solid overview of deliverability considerations for those using Salesforce Marketing Cloud to send email messaging.