I have some possible fixes lmk if they work
- Delete the EA app, reboot the PC and right click the EA app installer and run it as administrator
2. Make sure Controlled Folder Access isn't blocking the EA app in settings go to Windows Security < virus & threat protection < manage controlled folder access, if it is on either ads EA app as an allowed app or temporary turn it off
3. Run windows update if possible
4. Run terminal/Windows Powershell as administrator then run chkdsk and sfc /scannow (keep the space)
4. Try Origin (the old EA app), it is deprecated but still works, log in and try downloading Sims 4 from there. Once it's installed, the EA app should detect it.
If it doesn't work I will find more fixes