Hi Greg,
Am 09/05/2020 um 01.53 schrieb Greg Rose via Openrailwaymap:
Not sure why this shows it was posted by a separate user with my email address, but *I* posted this to the list.
You are posting from an @yahoo.com email address. Yahoo asks other mail servers by using the DMARC standard not to accept emails from Yahoo addresses which have an invalid DKIM signature.
A mailing list receives emails and resends them to the individual recipients. The mailing list modifies the subject (adding the prefix) and therefore breaks a signature (DKIM) which ensures that the email was sent by the original sender. (The signature ensures that only Yahoo can send correctly signed emails from Yahoo)
In order to make other email servers, e.g. Google and Yahoo to accept your email sent through the list, the list changes the From header. It is now: From: Greg Rose via Openrailwaymap openrailwaymap@openrailwaymap.org
Best regards
Michael