Exclamation Points (again) in Mail

Hello all,

I know this has been addressed, but the solution does not work for me. I get exclamation points next to servers on Mail for Mac, but when I use the "solution" to check the connections, the computer indicates that all of the servers are connected. Yet the exclamation points remain. It seems to be random at this point. Most of the time there are none, every once in a while they are back and the connection status is good. Suggestions on where to look next?