"There is a problem with your game setup. Please reinstall your game" error.

@keysh23  If you use a third-party antivirus, please disable it (temporarily) and repair the game in Steam; the option should be something like "Verify integrity of the game files."  Test the game once before reenabling the antivirus.  As long as you don't do anything else, your computer should be safe.  If this helps, set exceptions for TS4_x64, TS4_DX9_x64, and TS4_Launcher_x64; or the entire Bin folder they're in.  It's worth setting an exception for EADesktop.exe as well.

If this doesn't help, please run a dxdiag and attach it to a post.

https://help.ea.com/en-us/help/pc/how-to-gather-dxdiag-information/

I don't have any third party antivirus programs, and repairing the files doesn't seem to do much either.

@keysh23  I don't know whether this is related to the Sims 4 issue, but please uninstall the Acer User Experience Improvement Program (UEIP) App Monitor Plugin, which is crashing repeatedly.  You can uninstall through Windows Settings > Apps.  Restart your computer afterwards.

If that doesn't help, please try launching Sims 4 in DirectX 11 mode, or switch back to DirectX 9 mode if you're currently using DX11.

https://answers.ea.com/t5/PC/Enabling-DirectX-11-For-Sims-4-on-EA-app-and-Steam/td-p/13711976

If that doesn't help, please look for new errors in the Reliability Monitor.  Hit Windows key-R and enter "perfmon /rel" without quotes, and you'll see a chart of errors and updates with a column for each day.  Today is on the right.

Look for an error that happened at exactly the time of your most recent attempt to launch Sims 4.  If you find one, double-click it to see more details, then copy that info and paste it into a reply here.  If you don't see a new error, check back in an hour or so—the Reliability Monitor doesn't always update right away.

I tried everything here and nothing seems to have worked in my favor. I did try the reliability monitor earlier and came back right now to see if it was ever logged, but I don't think so. The only error that was reported around the same time looks like it doesn't have much to do with the Sims or anything with EA but I'm not too sure. 

@keysh23  Right, that shouldn't have anything to do with Sims 4.  It's another component of Acer software that appears to not be working correctly.

For that and other reasons, please try playing in a clean boot:

https://support.microsoft.com/en-us/topic/how-to-perform-a-clean-boot-in-windows-da2f9573-6eec-00ad-2f8a-a97a1807f3dd

The one service to leave enabled is the EABackgroundService, which the EA App needs in order to run.  Disable the rest as described.

When you reboot your computer, go through the Task Manager's background processes list shutting down any service that doesn't absolutely need to be running, for example anything from MSI Afterburner to RGB software might still be enabled.  If you accidentally kill a critical process and it doesn't restart on its own, just reboot your computer again.

Don't open anything other than Sims 4 and the EA App while testing, not even a browser window.

If this doesn't help, please repeat the test, except with your computer offline.  You can sign into the EA App and put it in offline mode, then disable wifi and/or disconnect the ethernet cable before pressing Play.

Please look for new Reliability Monitor errors after each test, and post anything you find.

Currently in the clean boot state, I disabled everything except for the EA app and tried to open Sims 4 but the same message. Also tried it with everything gone offline, no luck. Nothing new was logged on the Reliability Monitor except for the laptop not being shut off properly. Could it be something with steam?

Will uninstalling steam and having a new library also erase all my DLC?

@keysh23  It will uninstall your DLC but won't erase it from your account.  Your Steam account owns the content, not your computer, which means you have the right to reinstall it as many times as you want.

Hey, after trying everything, something finally worked and I'm able to play again! Uninstalling Steam along with everything else seemed to clean it all up. Thanks so much for your help, you're great!