That happens when you convert a pattern that was made with EA's Create-A-Pattern tool to a .package file.
A good rule of thumb is to always install Worlds, Patterns and Counters with the launcher.
The good news is that granthes made a tool to fix such a problem here (registration required to download)
http://sims3.the-prof.net/forums/index.php/topic,1808The bad news is that the site is down at the moment.