Sims 3 download installation failed

I recently downloaded a world for my sims in a place I've always downloaded cc from, and never had a problem with. It doesthe usual installing process, but then at the end it has the following message: Installation failed. Please make sure your game has the latest Software Updates and try again.

So far I've tried the following things:

• Re-installed the cc (deleted it from the downloads folder and installed it again)
• Cleaned up my mods folder (deleted new things that may have caused damage)
• Deleted extra and unwanted cc
• Checked for latest patches (there were none)

I've also seen a page resolving the problem, it said to re-download it because the game might not know the owner of the thing or something, but that did not work.

I don't think this problem should make me re-install the whole game, I've had worse problems and they did not need that much of a thing...

Please help me... I'm pretty sure I'm not the only one who has / has had this problem!!!

Thanks in advance...