Is there a way to show only unread messages in Yahoo mail?

My yahoo email is telling me that I have one unread message. But I don't see any unread messages! I know that sometimes there is a delay and an unread message pops up days later or weeks later. I've scrolled back through 2 months of saved email and there are no new unread questions. Is there a way to display only unopened messages, so I can find it? I have over 10,000 messages in my account, so far all of them seem to be read except for this elusive one. I can't scroll through hundreds of pages of email to see if I can find the one subject line in bold that is unopened. Ideas?