download your FREE* Red Carpet Collection by logging in to TheSims3.com with your account.

Yeah, same problem I'm having. It says "Please register Late Night... Do you want to register your game now?" Then if you select 'yes' and put in your serial code, it says "Code is Invalid". So I looked around until I found an update that says that Origin automatically registers the games for you on the Sims 3 site... which explains why the site says the code is invalid... but apparently, the store needs to be sent that memo. :P