May 2017 - last edited May 2017
Do you have a The Sims 3 expansion or stuff pack showing as installed in Origin, but not listed in the Expansions & Stuff tab in the game launcher? Here some steps that have helped other players in your situation:
1. Close Origin and the launcher completely.
2. Go to C:\Program files (x86)\Origin Games\The Sims 3 or to the folder where you have your game installed.
3. Delete the folders in there that correspond to the packs you are missing. Open the spoiler to see a list of the packs and their corresponding folders:
For example, if you are missing The Sims 3 Ambitions and The Sims 3 Into the future, you would delete the folders EP02 and EP11.
3. Open Origin. The packs will now show as not installed. Install them.
Once the installation has finished, check your launcher again
If your packs are still not in the launcher, please, take a look to this post: http://answers.ea.com/t5/The-Sims-3/Sims-3-expansions-missing/m-p/6085793#M222711