How to install Sims 3 from Origin

I purched Sims 3 University off of Sims.com. It told me the process in which i had to do in order to download. First I had to make an account for orgin, then download the program itself. Then I had to download the game, which went well. But then, I tried to install it from Orgin and its tell me that I have to choose a different file other that my data. HELP