Using Mailgun 1.3.1
HTTP API (Yes)
Domain Name verified
Got key
Test Configuration - result OK
Ironically, I changed to Mailgun so my WP site can send to Hotmail. I have a temp Hotmail account for test purposes–the hotmail address receives the mail from WP (yay!) BUT mail to my own personal email address does not get through, and I assume a bunch of other email addresses.
Tried switching to HTTP API "No" but that makes no change. (mail to Hotmail still works, and to my personal email address fails)
With HTTP API "No" and "Yes" I believe the config is good. Test Configuration - result OK
Any ideas please?