So it's taken since last July to work on this problem and a remedy is still at least a week away???
Although thanks for finally posting some kind of a workaround (it's taken 4 days and numerous calls and chats to customer support and this is the first time someone actually offered some real information), I already tested and set up another email account with a different provider to bypass the error (before your suggestion) so that I'm not losing more business/money every day this issue is apparently pushed aside by Cox. Hopefully that will at least help other users.
But there are important emails still locked up in the erred, closed Inbox that I need to access NOW, not a week or longer from now! I really do expect a credit on my account for this baseline, component service being down for the last 5 days.