I played a few days ago with .package and .sims3packs files installed, no issues. Today I decided to download some new cc, all of which were .package. Every time I tried to launch the game, it would crash when I clicked play, download, upload, literally any button. I uninstalled all CC and tried launching with a brand new file, worked. Reinstalled my saves, worked. Reinstalled all .package files, worked perfectly! The issue now is when I try to reinstall my .sims3package files, the launcher crashes the same as before, even when I try one at a time. I even tried to download a completely new .sims3package and still had the same issue, even with store content I downloaded directly from sims3.
