@puzzlezaddict Thank you for replying! Here are the answers to your questions:
So I guess there is something going on with my primary user account on Windows? I am running Windows 10 version 22H2 if that helps anyone else with the same issue.
@Hollymaze That's a good outcome, at least: since it's a local problem, you don't need to wait for EA to figure it out. I've still flagged your post and the others with the same error in case there's something else going on with the App. But in the interim, try uninstalling the App with Revo Uninstaller (the free version is fine). Restart your computer before reinstalling.
Please also delete all the folders listed here (post 223), if Revo doesn't find and remove them all itself:
https://answers.ea.com/t5/PC/CURRENT-ISSUE-Sims-4-already-running/m-p/13785451#M277450
The error associated with this leftover data was different at first, but the App is known for throwing new errors for the same underlying issue.
You can of course play in the new admin account for now if you'd like, and copy over any data you'd want to keep using, for example saves. Your computer has a Public folder inside C:\Users that's accessible from any user account, so it's an easy way to move around data without using cloud storage or an external device.
