To fix this issue, you should understand what (probably) caused it in the first place. The other day when I was having a problem logging into one of the websites I frequent, I decided to clear my browser cache. I have a feeling this event also wiped my SSL Security Certificate that my email was using.
As soon as I visited webmail.myemailprovider.com, it re-established my SSL Security Certificate. This seems to be the easiest way to re-gain that certificate for those of you who have no idea how to grab this certificate from the server itself. So give this a try if you're receiving this error but do not think it is a server configuration problem. I hope this helps somebody.