This evening I sent an email to a Cornell University address of someone, following a website interaction; I'd not written him before. I got this in reply from [email protected]
(anonymized):
<[email protected]> (expanded from
<[email protected]>): host
gmail-smtp-in.l.google.com[142.251.16.26] said: 550-5.7.26 This mail is
unauthenticated, which poses a security risk to the 550-5.7.26 sender and
Gmail users, and has been blocked. The sender must 550-5.7.26 authenticate
with at least one of SPF or DKIM. For this message, 550-5.7.26 DKIM checks
did not pass and SPF check for [gmx.com] did not pass 550-5.7.26 with ip:
[128.253.150.158]. The sender should visit 550-5.7.26
https://support.google.com/mail/answer/81126#authentication for 550 5.7.26
instructions on setting up authentication.
some-id-here - gsmtp (in reply to
end of DATA command)
Plus, my domain (gmx.com) is the 10th largest email provider in the world (as of 2022, according to Yahoo Finance). It doesn't make sense for Google to reject emails from it. PLus, I obviously can't setup SPF or DKIM for a domain I don't own.
So, what are people supposed to do? Tens of millions each need to setup their own SMTP service with their own personal domain, then setup SPF or DKIM for it?... Grrr.