This is for Sims3Packs that refuse to install in your game.
You need a program called S3r, made by the great Pescado, from this link. It makes the Sims3Packs into Package files, which take up less room in your drive and aare installed differently.
Here is an explanation of what it is and what it does, and a nice simple tutorial.
Remember to remove decrapified content before installing EA patches or new EPs and SPs.