Yahoo mail won't connect, but everything else works.

I'm trying to set up my new Macbook, and set up my "internet accounts".When I add my Yahoo email, AT&T actually through Yahoo, it connects and sets up my contacts and calendar. But email won't connect. When I try to select mail, it just spins for a minute and then stops.

Just FYI, when I set up this account as Yahoo on my iPhone, it works fine.

Any thoughts?