One domain has a small mailing list of about 200 users. The @yahoo.com addresses (and related, Yahoo-handled domains like old @att and @sbcglobal domains) are often just dropped.
Gmail addresses frequently go to spam, especially newly-added domains. I have found that having multiple @gmail users mark them as “not spam” tends to help, but not always.
My email server has had the same IP address for over 18 yrs, fwiw.
It's impossible to reach humans that can help. It's impossible to unlist. So I'm now on my third IP, my last one running mail for 4+ years, from Digital Ocean. Only now, occasionally, does an email get through.
I'm almost 100% confident that Microsoft just blanket blackholes or punishes anything from Digital Ocean or Linode.
The cost of swtiching IPs within those providers is low, so spammers have already abused that, and made life worse for the rest of us as a result.
Then I set up my own bare metal server and put it into a real datacenter serverhousing. I had couple of problems at the beginning and later once a few years later - problems sending to microsoft - but all those were resolved rather quickly via their forms. And I haven't had any deliverability problems since then.
The serverhousing I used is very strict regarding spam reports. I once tried to use the server also for sending newsletters (no spam lists, just emails which explicitly subscribed). Someone reported it as spam once and serverhousing contacted me soon after that they don't tolerate any spam. I explained that it was not spam and that there was unsubscribe link but I decided to not use it for any kind of marketing again. I think specialized services are better for this.
My "blacklisted" email company is Zoho because they consistently greylisted and blocked our correspondence with clients and have no one to contact to resolve email issues for senders.
Outlook/Hotmail is kind of stupid in this sense: if the first time, a new domain send an email they are very likely to flagged as spam. But if the user simply reply or send to that email, the moving forward hotmail won't flagged it. In other word, hotmail rely stringly
- is this domain new? - is this ip address start to send email new? - if I interact with this sender in the past
Seems thing with icloud and their proofpoint spam filtering.
gmail in other hand, has the best delivery rate, clear error message, great rate limiting and cool down period.
gmail is very smart, if we accidently send spam(due to our failure to filter out spam), gmail won't blocklist the whole IP, but hotmail/icloud does.
And the process to delist from them homail/icloud are just absurb. I'm unable to contact their team.
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I'm starting a new company where email connection to my user base is essential. From time to time I also need to sen all users certain notifications which looks kinda like marketing email but isn't.
Could you contact me as I would like to ask your opinion on the configuration that I'm trying to set up. I would also like to discuss your experiences.
If isn't too much, you can reach me by email at [email protected].
sendgrid is dirt cheap for transactional emails. And there's tons of offerings for marketing emails; I'm partial either to sendinblue or ses depending on your use case.
There really isn't much reason to roll your own, particularly with ses.
In my personal experience, over five years of running my own business and personal email entirely and another decade and counting since of running PBXes that directly send voicemail messages, Gmail has only explicitly blocked me once, and that was 100% legitimate because the site the PBX was located at had an infected PC. It occasionally will filter messages to the spam folder, but that almost always means one of the users actually flagged a message.
I could send an email to myself from a bogus address via raw SMTP over Telnet to port 25 and I'd be willing to bet my week's pay that Gmail delivers it. They might mark it as spam, but they deliver reliably.
Microsoft on the other hand is a massive pain in my ass. They usually work, but about 4-5 times a year they seem to randomly pick one of my systems to treat as suspicious and block emails from. The process listed in their block message always works, but it's annoying to have to deal with regularly, especially with no rhyme or reason.
Yahoo is the worst, they straight up block everything I do with no recourse. I have one user who insists on using his Yahoo email and I basically had to tell him we don't care that Yahoo won't accept messages.