I am trying to get mail properly setup, and am able to send mail. The problem is that DKIM / SPF is failing because the return-path / envelope sender isn’t being set. It is defaulting to my user account on my hosting server, rather than being properly set to the same address used in the ‘From:’ field.
I’m somewhat out of my depth here, but my host provider’s tech support thinks it is an improperly implemented mail() function.
Here are the example headers from an email sent from Backlight:
Return-Path: <kylelucy@SERVER-FQDN> From: Kyle Lucy Photography <email@example.com>