If I have The Sims 3 Seasons game and I buy the Sims 3 Generations game will I need the Seasons or Generations disk to play?

the game always looks for the newest disk you install in your case seasons for example i can put my games in like this sims 3 gen uni late night seasons ambitions but as seasons is the newest one that's the disk the game needs to run

if your seasons game is registered with origin you can download the digital version of seasons and play

you will need to manually uninstall the seasons disk files

https://help.ea.com/article/the-sims-3-seasons-manual-uninstall

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