Mail error message

I keep getting this error message in Mail.

The server returned the error: Connections to the server “p50-imap.mail.me.com” on the default ports timed out.

I cannot find the problem. I've logged out of iCloud and logged back in, still the problem. I haven't changed any settings. If I Quit Mail and re-open it all of the deleted email messages reappear.

Ideas?