We have been made aware of an issue you may encounter while trying to save your game after installing The Sims 3 World Adventures or updating your game. The Sims 3 World Adventures and the Game Update have changed the way your save files are created, which can lead to an error during your gameplay when you save your game. If you encounter an error that says “Error Code 16,” please use “Save As” to save your game instead. This will allow you to create a new save file and circumvent this error.
If you are beginning an entirely new game or starting in a new neighborhood, you will NOT encounter this issue.
We are working to address this and will update you as soon as possible.