Hi
I hope you don't mind, but any email platform which accepts email without login credentials (username and password) is classed as an open relay/system, so credentials should be presented.
The from email address can however, depending upon the provider, be a different email address from the credentials used
Also, on our enterprise clusters, if there is no subject or return email address (i.e. Null), it is either immediately rejected or send straight to spam).
There is only 1 exception to the above, which could only be set by the system admin, and that is if it is whitelisted. So at which it is directly delivered
I stress though, not many people would have this option as to run your own enterprise mail server costs a lot of money, and takes your time up
@roseway sorry I do not use email alerts, but if I did, our connections are whitelisted.
It does sound as though dray had a blank sender though, but it's late and I could be wrong so I apologise in advance
Many thanks
John