"There was an error during startup. Please see the Log for more details

[puzzlezaddict]

@ImposibleGirl314  Try using CCleaner and/or Revo Uninstaller to remove all traces of Sims 3 (and any other affected games) from your computer.  Both have free versions that work fine, although it's always possible that one of them misses some files or registry entries.  Then restart your computer, install the base game from Origin, and see whether it loads.

[Noonymoo]

https://youtu.be/TyIta8i5nuc Follow this video It actually works. ( for anyone on Windows )