My smart mailbox keeps telling me there is one last unread mail in there, even though it is empty. I have this one set up to read all my unread mail: that's the only rule & purpose for it. What have I done wrong? Regards.
I deleted the whole Smart Inbox and then re-created it and it was still there.
It turns out it's a common problem with Mac, and Maverick may have fixed new instances. But if there were existing older instances of it Maverick, would not have deleted those. So use these hints anyone!