Okay, in the last couple days, several of our users have not been getting registration verification emails...and from what I can tell, our admin haven't been getting the emails either. This is only something that has apparently been happening for the past 24 hours or so, so we're a bit confused. It also doesn't appear that our 'Email Post' feature is working, either.

I couldn't find any actual reason why the system would be messed up like that, but I was wondering if these email issues could all somehow be related? Also, we are still running 7.2.2, so if that is somehow related to the problem, that's easily fixed with an update. But for now, we're stuck...

If it just stopped sending out emails, and your on a hosted server, then you'll probably want to contact your host. If this is your own server, then you can watch the mail logs when you try to do something like Email Post and see if it gives any info as to what's going on.