"Unable to start: The Sims™ 4 is already running. [ed35e0ea:29f00e76:00000000:

@cmyles1993

Move your Sims 4 folder from Documents > Electronic Arts to the desktop and launch a brand new game. Quit and then move the contents of the save and Tray folders into the newly created Sims 4 folder in the Electronic Arts folder. Make sure you move the contents, NOT the folders themselves. You can also do the same with your Mods if you use them.