"Reminds me of this: "The Hostile Email Landscape," by Jody Ribton http://liminality.xyz/the-hostile-email-landscape/
In summary: Start sending email from a new mail server and the established players will likely mark it as spam. Market captured."
Oh because it most likely is?
Oh and I wonder why people use gmail, between having to use tools that are absolutely user unfriendly and a hosted solution, the option for 99% is clear.
(However I don't advocate using gmail/google apps)
"Earlier this year I moved my personal email from Google Apps to a self-hosted server, with hopes of launching a paid mail service à la Fastmail on the same infrastructure. I've done this before, and this server was configured perfectly: not on any blacklists, reverse DNS set up, SPF, DKIM and DMARC policies in place, etcetera. (Side note: https://www.mail-tester.com/ and Port25 are great for checking your setup.)
I had no issues sending to other servers running Postfix or Exim; SpamAssassin happily gave me a 0.0 score, but most big services and corporate mail servers were rejecting my mail, or flagging it as spam:
- Outlook.com accepted my email, but discarded it.
- GMail flagged me as spam.
- MimeCast put my mail into a perpetual greylist.
- Corporate networks using Microsoft's Online Exchange Protection bounced my mail."
And the 'hints' are pretty strong it isn't
At the same time sometimes there are some gotchas that people might not be aware (and things that the big providers have to deal with and that to them are sign of spam - this should definitely be more publicized, however they want to protect this because of the actual spam senders)
Now, if their domain previously sent mail, then now it gets from a new domain this might make warnings go off
Politely contacting those email providers might help
One small anecdote: I've had Gmail flag (legitimate) mail from 'google.com' not only as Spam but as Phishing as well.
Really? Anybody who tried contacting Google and/or Outlook.com to claim some e-mail server is legit cares to comment? Is it possible? Is it different than what the article I've liked claims:
"The standard response from all of the above boiled down to this, from Microsoft's Postmaster Troubleshooting page:
- IPs not previously used to send email typically don’t have any reputation built up in our systems. As a result, emails from new IPs are more likely to experience deliverability issues. Once the IP has built a reputation for not sending spam, Outlook.com will typically allow for a better email delivery experience.
How to build a reputation for not sending spam when they're already flagging, bouncing, or deleting my mail was unclear."
- Have people click 'not spam' on the email in GMail/Outlook
- Have people send email from those domains to yours
1) The individual IP address(es) used by your server were used for spamming/phishing/bad things.
or
2) The larger address space owned/used by your hosting company is seen as sullied.