Recently, I started noticing that emails sent from php or forums using it to addresses hosted on the onmicrosoft.com domain did not deliver. I swiftly realized that sending it to the alias on our own domain (say [email protected]) did not work (they got sent back with that "Delivery Notification" thing) and that I instead had to send it to the original (e.g. [email protected]).
These e-mails do not get send back to the system with the message of being impossible to deliver, but they still don't get delivered. There is no trace of them. All the logs say they were sent successfully, yet they are gone.
Anyone got any clue on what may be causing this? I heard LTT's forums had issues with it, too.
No my code isn't wrong. I tested with other addresses.