Since the Sim 4 updated and added the marketplace, I was having the "failure to launch" issue. I waited around for the next update to fix things, and had seen some people say their game was now working. My game will load into the main menu but when I try to play it just goes to the loading screen forever and never loads.
gunnierto Does this happen with a new save too? Please test for comparison's sake and let me know. Try it with your Mods folder removed if there's anything inside other than Resource.cfg.
If the new save is affected, 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.
