CUSTOMER: I'm having a problem with your web browser.
KING: Please describe the nature of your problem and the steps you've taken to try and resolve it so far.
CUSTOMER: Well I can't get it to load any websites. Firefox is fine, Chrome is fine, but any time I try to load something on Internet Conquistador I get a "cannot connect to server" message. Ie ven deleted my browser cache, and--
KING: Sir, I'm going to try to help walk you through this, but I have to ask you a few questions first. Have you tried deleting your browser cache?
KING: OK, I'm going to show you how to delete your browser cache.
This conversation is nearly identical to the one I had with Kobo support, only "I'm having a problem with your web browser" is replaced with "your site tells me my epub is invalid" and "delete your browser cache" is replaced with "run it through an epub validator."