Do you have the installation codes?
If you do, I'd register all of the codes on Origin, and if Origin accepts them, uninstall Sims 3 completely and then download and re-install via Origin. In this case, you won't be using the CDs -- the launcher probably thinks something's wrong with them. Or, you could download and install Twallan's NoCD mod.
I actually disagree with pallyndrome's suggestion as this usually leads to a conversation like this:
EA support: Well, since you bought it from a store, you should go to their customer support and not ours. *refuses to help whatsoever*
Real Store: Well, this isn't our fault. We don't make the games, EA does. Go to their customer support.
...And that conversation keeps going and going.