[RndTbl] Gmail spam filtering super-aggressive lately

[Alberto Abrao]

I wonder what'll happen with this one...

Alberto Abrao
204-202-1778
204-558-6886
www.abrao.net

On 2020-04-02 3:27 a.m., Trevor Cordes wrote:
> On 2020-03-31 Alberto Abrao wrote:
>> Does anyone have any idea of what should I change on my end? That's
>> weird.
> Looking at your DKIM settings in your headers, I think I spotted the
> problem.
>
> Alberto's:
>   h=from:from:sender:reply-to:subject:subject:date:date:
>   message-id:message-id:to:to:cc:mime-version:mime-version:
>   content-type:content-type:content-transfer-encoding:
>   in-reply-to:in-reply-to:references:references;
>
> Mine:
>   h=Date:From:To:Cc:Subject:In-Reply-To:References;
>
> You are trying to protect too many headers, *especially* the ones that
> mailman needs to change.  Also, the case on yours is not RFC (though
> probably doesn't matter) and many headers are duplicated (weird!)
> indicating a misconfiguration.
>
> Find your DKIM settings and try shortening your protected headers to a
> list like mine (above).  And fix the case, and duplication.  Any header
> not listed will not count in DKIM's hash of your email.
>
> Critically, I think you need to make sure you do NOT have "sender:"
> protected, as mailman will always be adding/changing that header, and
> that will throw off the hash and DKIM verification.
>
> MUUG's mailman may also play with the content-*.  That's why I'd stick
> with a very small set of headers.  Spammers can't really make use of
> those extra headers anyhow, so they don't need to be protected.