copy the "sims3launcher.exe" file in the sims 3 folder(the one with the launcher problem)don't replace old file but just rename it or another option You can also fix it by entering your SimS 3 DVD in your drive and going to my computer and Exploring the icon, Open Game then BIn and copy Sims3launcher.ex_ and rename it to sims3launcher.exe and replace it the same way you did.
You dont need to save the old file since its corrupted anyways.