Uninstall your most recent EP then download and reinstall the digital version from Origin. Instructions here.
I have the Sims 3 seasons (and a few other expansion packs but seasons is what I'm playing on) and when I try to play the game it says that the disk isn't inserted and when I hit reply the same error keeps popping up. I just installed OS X El Capitan on my computer and thats the only thing I could think of that would affect my game. The same thing happened to one of my friends and she also has a macbook computer. This problem is really annoying so I would appreciate it if someone can give me an answer as to why this is happening and how to solve the problem. I was just playing the game yesterday before I installed the update so I know its not my game.
I have moved your post to this stickied thread specifically related to your disc error issue. Please read the opening post for further help.
