Re: What must one do to avoid Gmail's retarded non-spam filtering?

Have you tried DKIM signing? All email sent from Gmail is DKIM signed, so they probably also support checking it and a valid signature may lower your spam score. DKIM is definitively a must have for gmail.

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At least this isn't Hotmail where mail is just silently deleted with no NDR after it's accepted by their MTAs. If Hotmail is doing that to your messages, you're in a quite bad

posture. That's their way to tell you "we don't like what you're sending at all". Did you consider hiring deliverability consultants? I'm afraid there is no magical way to reach inbox without a audit of your process and systems. Benjamin