After years of having no problems with admin receiving new registrations alerts from miniBB, the alerts suddenly stopped arriving today. And I also noticed that my site's contact form script (unrelated to miniBB) was also not working properly (i.e., no messages were being delivered even though the script would execute fully without errors).
My web host's tech support told me that they had been gradually applying a "sender domain policy" on to all of their servers since last year. This new policy requires emails sent through my web host's mail and web servers to use a "From" address that is hosted by my web host. In other words, emails sent with a "From" address hosted somewhere else (e.g., Hotmail or Google) may be blocked.
Later I found in my Maildir a series of returned mail many undeliverable "new user registration alert" (to forum admin) messages. Below is part of the mail header of one such "bounced" message: (I have changed the email addresses to protect the innocent)
So, I did a couple of tests and signed up using a couple of different email addresses; and below are the results:
a) Test using Yahoo address: received new account validation message, password reset message without problem.
b) Test using own domain email address (hosted by my web host): did not receive new account validation message. Did not test password reset message, as I just assumed it would get blocked as well.
In both a) and b), email alerts to my miniBB's Admin user all got blocked (i.e., the alerts never reached my miniBB's Admin mailbox hosted by my web host).
While nobody will die if alerts don't reach Admin, but it would be a convenience lost for Admin not to be able to receive notifications ... is there a way around the problem? As always, any advice/help you can offer will be gratefully received!