Why can't i connect to any minecraft servers?

I currently run 1.7.2 and when i click multiplayer and open the server panel All OF THEM ARE RED AND SAY: Can't connect to server. It didn't do this before! How can i fix this!

Yours is robably a fake downloaded free full version
i had the same thing. It doesn't work
if your is actually bught and is original try downloading it on a another computer and connecting. If it wirks then it is a problem with the platform