I’ve been struggling with both Spectrum and Microsoft for about a month or so now, too. I host a small site for a non-proft that I’m part of on a Droplet that I otherwise use for personal hosting. I run a few mailman lists for the organization that we use to send maybe 200 emails/week to our members, if we’re lucky. I’ve been doing this for a few years and have become quite familiar with all the mail-related acronyms: RDNS, SPF, DKIM, DMARK, and everything is in order and the server itself is not blacklisted anywhere that I can find.
With our predominant local ISP being Spectrum (formerly Time Warner), we have lots of members using their RoadRunner email accounts, which was the first ISP where I noticed issues. Unfortunately the error message Spectrum returns is simply “SMTP server unavailable,” which is completely unhelpful, especially when I can send from another (non-DO) email address with no problems whatsoever.
I am a Spectrum customer myself, so I have an email address with which to test. I’ve tried reaching out to support, but I get nowhere. Emails to various postmaster@, ubblock@, etc. addresses either bounce or go unanswered.
What cued me in to where the problem actually lies was when hotmail and outlook.com mail started bouncing. Microsoft provided a bit useful bounce error message indicating that we were blocked because of a wider block on a range of IP addresses. With some searching, I came across this form, and I got an email within less than 24 hours indicating that we were “conditionally unblocked.”
Spectrum is still an issue. I’m now thinking that I may move the non-profit’s site onto a server I have with a different host to see if that makes a difference. I don’t want to do that as the DO server has better resources, but not being able to send email to Spectrum, as much as I want to tell all of our members to switch to something better, is a real deal breaker. We have no real budget for web/email services, so going to a dedicated email provider really isn’t an option for us.
So my concern here has started to move toward panic. We just got blocked by the msn.com and hotmail.com. The message clearly states that a range of addresses at our ISP are being blocked rather than an issue that is specific to our email sending. When I check our logs, outbound to msn.com and hotmail.com is small, but even one password reset confirmation not getting through is enough to be a problem. We have no problems for years and now we have encountered a couple of major blocks within the last few weeks. Has anybody else noticed a significant increase in email deliverability problems recently? Does DO have something significant going on here?