July 2022 - last edited July 2022
@Rosey313 What kind of error do you get? Please clear Origin cache and try again.
https://help.ea.com/en/help/faq/clear-cache-to-fix-problems-with-your-games/
July 2022
That did not work getting the following error
"This product requires an installed copy of the Sims 2. Please install The Sims 2 before installing this product "
July 2022
@Rosey313 That sounds like you're trying to install an Expansion/Stuff Pack for The Sims 2. The Sims 2 Ultimate Collection contains the base game and should not produce that message.
However, installing The Sims 2 Expansion/Stuff packs separately has not been an option in Origin since around 2015, which leads me to wonder whether you're trying to install something else, such as The Sims 2 Store Edition. Please double check what it is.
July 2022
@Rosey313 , The Sims 2 Ultimate Collection contains not only the base game, but all the Expansion Packs and Stuff Packs released for Sims 2. If you own Sims 2 UC, you shouldn't have to install any additional content unless it's a mod or CC.