Emails Not Sending

I have followed everything in the article and my emails still aren’t sending. They sent fine the first year I had the plugin. I tried switching the mail type, I contacted the hosting provider, tried sending an email to just myself, hecked spam and all other folders, etc.

It says that it’s sent. I see it in the ‘sent mails’. So what the heck could be going on?

I have not switched my layout or made any major changes to my site. ??