Marshmallowycat To be clear, the game didn't start but threw no error message when you reinstalled it into the new account; and then it threw the service initialization error once you applied the patch? Please repair the game in Steam; the option is called "Verify integrity of the game files" and should be somewhere under Properties.
Try again to play, and look for a new error in the Reliability Monitor. Hit Windows key-R and enter "perfmon /rel" without quotes, and you'll see a chart of errors and updates with a column for each day. Today is on the right.
Look for an error that happened at exactly the time of your most recent attempt to launch Sims 3, specifically after repairing. If you find one, double-click it to see more details, then copy that info and paste it into a reply here. If you don't see a new error, check back in an hour or so—the Reliability Monitor doesn't always update right away.
