@vgreg92 What kind of install is this: EA App, disc, Steam, or something else? Did you happen to temporarily uninstall any expansion or stuff packs at any point? Do you use some kind of cleaner app that removes registry entries or anything like that? It might have removed something critical for Sims 3 that it mistakenly flagged as a duplicate.
Installed from EA app with all expansion packs.
@vgreg92 First, please repair the game in the EA App: open your game library, click Sims 3, and select Manage > Repair.
Next, if you do have a 12th-gen or newer Intel processor, please run the Alder Lake patch again, applying it to TS3.exe, without the W, since you've installed through the EA App. If you don't have an affected processor, don't bother. And if you use a third-party antivirus, disable it (temporarily) before running the patch. As long as you don't do anything else at the same time, your computer should be safe.
Finally, if OneDrive is running on this computer, whether you deliberately use it or not, please pause syncing. You can do so by right-clicking the cloud icon in the lower-right corner of the screen.
Please test Sims 3 before reenabling your antivirus, and if it works, you can set exceptions for EADesktop.exe, TS3.exe, and Sims3Launcher.exe, the last two without the W.
I did everything you've written but the problem is the same. ☹️
