I noticed one of my WordPress websites wasn’t sending me email alerts from a couple of plugins I had installed.  It was a test website which was hosted on Azure so it didn’t have a domain name.  I figured the email was being deleted as junk email.  I was thinking of use a STMP transactional service but really not worth the cost for a test website.  I decided to research if it was possible to use the email domain I was hosting at Office 365.  Using the resource below, Office 365 gave the needed info to configure the STMP settings in a WordPress plugin.  I sent the email to that email domain and email is arriving.