FWIW, I was having issues with emails triggered correctly but not being received for new user registration email. My site is on GoDaddy shared hosting (linux/cpanel). I am not using any SMTP plugin … only Better Notifications for WordPress plugin.
After reading https://betternotificationsforwp.com/documentation/getting-started/how-to-improve-email-delivery/ … I called goDaddy tech support and was directed to this article:
https://www.godaddy.com/help/add-an-spf-record-19218?v=1
for the TXT value I used the suggested setting: v=spf1 mx -all
AND ALL IS WORKING FINE!
Hope this helps someone out there ??
