It is now Dec 18, 2013 and I had the same problem. My POP3 account worked fine but as soon as I switched to IMAP, my emails disappeared and I couldn't receive emails on my Mac Mail, but I could with my iphone. Also, once a day my emails will be wiped out. When I tried to set up my POP3 account again, it wouldn't let me. Account settings are only IMAP. So beware of deleting your POP3 account. You will never get it back.
Also, when I called COX (several times and several hours later), they did not acknowledge that it was their problem. They said I had some incorrect settings or that possibly my account was hacked and that was why my emails were disappearing.
