FAQ store worlds and how they work http://answers.ea.com/t5/The-Sims-3-Store/Guide-Sims-3-Store-Worlds/td-p/1589911
- Go to thesims3.com and log in with your account
- Go to your account page: https://store.thesims3.com/myAccount.html (site will ask for your password again)
- Click on Redeem a Code
- Enter the 16-letter code, accept the Policies and click on Redeem
- Go to your purchase history to download the world (make sure your game is updated to the newest version)
OR
- Go to thesims3.com and log in with your account
- Go to the general redeem a code page: http://www.thesims3.com/incentive/generalredeem.html
- Enter the 16-letter code (this is not for 20-letter codes) and click on Submit
- Go to your purchase history to download the world (make sure your game is updated to the newest version)
Disc or Code in a box
Depending on which world you buy, this works a bit different (see below). There are always codes in the box though and you can follow the instructions for Origin to redeem those.
The disc installation process skips over instead of installing
Not sure what's up with that but try to redeem your code in the store and download from your purchase history instead.
The world doesn't download
The most common reason for this is that the game is not updated to the newest version. Make sure you are updated.
The installed world doesn't show up ingame
Sometimes the world doesn't get installed correctly. Try installing it again. Also if you tried installing through the launcher, try the ingame Store instead or the other way round.
If that doesn't work, Try reinstalling all Store Content following the method here: http://answers.ea.com/t5/The-Sims-3-Store/FAQ-The-Sims-3-Store/td-p/333394/.
The game still wants me to buy the world
Sometimes when you start the game you see a little money icon next to your world although you already bought and installed it. This is just the ingame store not recognizing properly that you have already bought it.
Scroll down further down the list to see if there's a second version that doesn't have the icon to start a new game with. You can also turn off the ingame shop in your options and then it should only appear once. If it doesn't see above.
Invalid Serial Codes or Serial Code already used
If you get an message that your code is invalid, you need to contact a customer support game advisor for a new code. This can have several reasons. Trying to redeem those codes on Origin can for example invalidate them.