abrogard wrote: ↑Tue Apr 16, 2024 11:20 pm
An email just arrived from saconveyancer congratulating me on the board being correctly set up. That's not the 'test email' is it?
Yes, the "Send a test email" button in ACP sends a message containing at minimum
"Congratulations. If you received this email, phpBB is correctly configured to send emails." Whatever you put into the additional "Message" box under the "Send a test email" button, if anything, will appear as an additional paragraph in the test email. This free-form additional "Message" content allows you to keep track of which test you actually successfully received, by allowing you to put information such as
"Test at 13:30" or
"Test after turning off Verify SMTP peer name" into the actual test email.
Agreed that "the other phpBB board instance was not attempting to use SMTP" is only the answer to "why I wasn't getting the same PHP Warning", and is not an indication of what SMTP or PHP mail() configuration will be required in order to successfully send email from the server where your phpBB instances are being hosted.
Consulting with your host or at least their documentation may be necessary to determine what exactly they expect or require for PHP applications running on their servers to send email, whether by SMTP or using the PHP mail() function. e.g. Your host might require that you're using a particular "From:" address in order to allow the mail through on PHP mail(); or maybe they do require or specifically do not support TLS/SSL for the internal SMTP server; maybe they expect you to use "localhost" as the DNS name instead of their "external" SMTP server, etc.
No one answer is correct for everyone, and you have to determine what your host provides or requires. Sometimes they can be pretty picky or non-obvious, because your host is trying to prevent their servers from being used to generate spam email. You can of course just keep randomly testing until you find something that works, if the host or their documentation is not particularly helpful. Don't share any passwords, but if you share what your host's documentation declares regarding the configuration needed for a PHP-based application to send email from their servers, we may be able to help with additional more specific suggestions.
Using the "Send a test email" is sufficient for testing whether or not the emails "are going through at all" based on the current phpBB email settings. Once you determine the SMTP or PHP mail() settings that allow the test mail to arrive consistently, then you can move on to testing actual user creation and the notification email expected in that situation. I've normally just deleted the test user and then tr-registered exactly the same username and email again, as opposed to accumulating multiple unique test user accounts.