I am in Las Vegas, NV, a 20-odd years customer of Cox, and this is my problem too, exactly.
It started last Monday, April 10. My Thunderbird could send but not receive mail. I first thought perhaps it was some Internet connection problem but the usual nostrum of turning the Modem/Router off and on and even computer restart did not help. Ping to POP.COX.NET server got automatically redirected to POP3.EAST.RS.OXCS.NET and timed out. Ping to IMAP.COX.NET and SMTP.COX.NET worked though.
I had several chat sessions with the Client Disservice. The first one ended with the soothing message "I was able to confirm that the pop.cox.net server is having a little update and we hope that by the end of the day this issue is fixed". Of course, nothing happened. Such "little updates", translation - fixing what ain't broke - always spell trouble. The other sessions were also equally frustrating and their basic premises were (a) there was no problem at their end, (b) I was a fool and (c) my software (Thunderbird) needed a reset. Unwilling to engage in a time-wasting, fruitless and aggravating wild goose chase, I terminated the chats, keeping their transcripts.
Although IMAP.COX.NET was pinging, switching the server to it and the port to 993 as instructed by some Internet websites did not help.
So this morning I shot a snail mail to Mr. Len Barlik, Executive Vice President and Chief Technology Officer, Cox Communications, Inc,, 6205 Peachtree Dunwoody Rd, Atlanta, GA 30328 (an address I pulled from their confusing and convoluted website) recounting my woes and hoping for some help from the top echelon which is always an uncertain prospect. I still remember how a few years ago their SMTP server had acted up and sending mail had stopped but Cox stubbornly refused to admit that there was a problem and after a week-long period of frustration the service magically resumed without any changes at my end and with no apologies or even an explanation from Cox.
Yet another problem has now cropped up. When I try to access this board with Firefox, I sometimes get this mysterious message "Bad Request - Request Too Long HTTP Error 400. The size of the request headers is too long." After several failed attempts to log on I switched to Internet Explorer and succeeded, for now, anyway.