I would caution against purchasing any product from Kaplan. They have terrible customer service, and will not respond if you have trouble with their online service despite your spending of hundreds of dollars for their products.in reference to: Welcome to Kaplan Test Prep and Admissions (view on Google Sidewiki)
It turns out nothing is formally wrong with their site. What is wrong is that if you've entered your username wrong, rather than inform you that there is no user with that username, it merely logs you in to a new account. However, it doesn't tell you that you're in a new account without a paid subscription. Perhaps some savants are capable of keeping track of all their usernames and passwords. I am not, nor do I think most people are.