Where are you trying to downoad from ? The Sims 3 Store purchase history: https://store.thesims3.com/purchaseHistory.html ?
Is your game updated to 1.67 ?
See this guide for further help: http://answers.ea.com/t5/The-Sims-3-Store/Guide-Sims-3-Store-Worlds/m-p/1589911
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