Subject does most of the work here, but I'll expand. [edit] Maybe if I had just RTFM'd harder I would've found my answers... I think this will help, but leaving the post up in case anybody else has ...

I found a good reference located at https://docs.microsoft.com/en-us/ex...-send-email-using-microsoft-365-or-office-365 I've been using "option 2" for a while now ...