Stuck in loading, more like game crash.
One situation: I launched my game, and all went well, and here we are at the home page, I tried to click on something to close the Ad page, but once I clicked, my screen would flash one or two times, then It get stuck, I can't close my game unless using my task manager.
Another situation : I launched my game, and it get stuck directly at the first loading page which is an all white page and the icon of my mouse shows it's 'loading', but still I'm stuck with that too, I can't close my game without task manager.
Usually It wouldn't give me a code error, but once I got 135dec40:598068e4:00000078:37b26003, I tried to fix the problem according to the support on Forums but I tried all, It didn't work.
Emonsean As a test, please try playing in a clean user folder. Move the entire Sims 4 folder out of Documents > Electronic Arts and onto your desktop. When you launch the game, a clean folder will spawn with no content. (Your saves and other content will be intact in the folder you've moved but temporarily unread by the game.) Don't add anything to the new folder yet; just start a new save and see how it runs, that is if you can get that far.
If that doesn't help, please provide a dxdiag. Click Windows key-R, enter dxdiag in the run box, wait for the scan to finish, click "Save all information," and save the file to your desktop. From there, you can attach it to a reply using the paper clip (Attachment) icon included with the other formatting buttons.