June - last edited June
@kurtiford I've split your post into its own thread, since the other thread was quite old and about a different subject.
Click on the Sims 3 icon in your Origin library, then select More > Expansion Packs, and scroll to where Late Night is listed. What does the orange button say? If it doesn't say Download, try clearing Origin's cache, and if that doesn't help, uninstalling Origin "the hard way" and reinstalling.
If these steps don't help, please let me know. The latest Origin build is causing TS3 problems for several players, and we don't yet know why, but more information is always helpful.