Earthlink Webmail Down.
Earthlink offers the following as a possible solution:
“If you’re using Internet Explorer to check your email, click Tools > Internet Options > Connections (tab) and make sure Use HTTP 1.1 is selected and Keep-Alive is selected.”
Read About the article: Earthlink Webmail
What does this mean?
It seems like these are all settings configured at my ISP level and not something that I should be changing on my PC.