SIMS 3 MEDIEVAL (Will not open)?

I downloaded the sims 3 medieval last night directly from the EA game downloader. I haven't been able to play it since. It keeps telling me " To run this application, you must install one of the versions of the .NET framework V4.0. Contact your appllication publisher for instructions about obtaining the appropriate version of the .NET framework" I went online and downloaded the 4.0 .NET framework, and nothing new has happened.. What should I do now?