I had problem that cannot open leed online v3 on my mac for a long time, even though I already have the newest adobe reader version. If anybody has the same problem you may check the following link: https://www.leedonline.com/irj/go/km/docs/documents/usgbc/leed/config/common/login/checkAdobePlugin.html
You seriously rock. I think you fixed my problem with this post. A thousand thanks, Diana Hill, whoever you are. I wish I could send you flowers.