My Sims 3 launcher nor downloads are not working.

I recently tried to download new pieces of CC for my Sims 3 game y'know, as most do, but when I go in to try and download them, a black box shows momentarily before it disappears, and nothing is downloaded. Same goes for launching the actual game, but it's a black screen. I've tried EVERYTHING from the forums, closing the apps on the taskbar, repairing the game, and even uninstalling. SOMEONE PLEASE HELP. Thanks :3