Receiving a "You have been unsubscribed" email when not actually unsubscribing

[Jonathan H]

On 19 April 2016 at 12:13, Stuart Henderson <stu at spacehopper.org> wrote:

> Another likely reason: gmail hates mail delivered over v6.

More likely to be that the domain is broken and outgoing email isn't
setup to meet current standards...

http://mxtoolbox.com/domain/lists.infradead.org/
https://toolbox.googleapps.com/apps/checkmx/check?domain=lists.infradead.org

No DKIM? No SPF? No DMARC? Primary Name Server Not Listed At Parent?
Remote domain could not be found?

I'm amazed ANY mail gets in or out at all!