Hi Perry,
The PHP mail() function (not SMTP) is used for confirmation, welcome, and notification messages. I suspect this is where the problem lies. I do not know why it would work and then stop working - maybe your host's mail queue is full of messages and it will be delivered after some time. If it never comes through I highly recommend talking to your host about the reliability of the PHP mail() function.
Here's a test script you can copy to a .php file and upload/browse to on your site. Please set up the $domain and toaddr variables to your ListMail domain and destination test address.
<?php// config$domain = "domain.com";$toaddr = "test@listmailpro.com";// end config$fromaddr = "mytest@$domain";$returnpath = "bounceme@$domain";// codeecho date("l, F jS g:ia T");echo "<br>testing mail() function..<br>sending mail.. ";if(mail($toaddr,'mailtest','mailtest',"From: \"Mytest\" <$fromaddr>\nReturn-path: <$returnpath>")) echo "mail seems to be sent ok<br>"; else "mail NOT sent ok!?<br>";?>
Regards