My client's blog was running perfectly until about a month ago, when the comment notification emails suddenly stopped showing up. We thought the notices were getting caught in spam filters, but after checking our mail server, it seems they aren't going out from WordPress. I've tested a myriad of configurations and settings with no luck ... I can't for the life of me get a comment notification to show up, regardless of the email address I use. (We've also looked at their Exchange server and no incoming WordPress messages are hitting the server.)
I also added a plugin to notify multiple email addresses, and those emails don't show up, either.
The site is hosted at Godaddy (grid hosting) and I spoke with them as well ... they claim that we are fine, that our PHP mailer is fine, etc. They said it must be a WordPress issue. (The Exchange server hosts told me to call Godaddy.)
I see quite a few other unresolved threads with the same general "comment notification emails suddenly stopped working" theme. Can anyone out there help out? I see a lot of information about wp_mail and phpmailer, but I have no idea what to look at/change, or why this problem would have cropped up when we didn't touch anything in the setup or at our web host.