Ok, I have the base game, world adventures and ambitions. Now, I tried to download the Weapon's System and I couldn't drag it to inventory. I tried all of the steps and it still wouldn't work. Now here's where it got bad:

I deleted my whole mods folder in My Documents and Program Files. Then I tried to run the game. The screen would go black with a white outline around the screen and then crash back to desktop without an error message.

Then I tried reinstalling my expansion packs (only the expansions because I can't find Sims 3 ) World Adventures said something about a cylidrical error and it wouldn't install. Then I reinstalled Ambitions without any errors, well until I tried to load it and the black screen crashed again without an error... Apparently. Then I went into my program files and discovered that there was a World Adventures folder anyway. So, figuring it wouldn't do any damage, I deleted it .

Now whenever I try and load the game launcher to start my game it says, "There was an error during startup. Please see the log for more details." All I can say to myself is, " "

Please help me, I'm reaching the end of my rope and I'm meant to get Late Night this weekend and I can't play it if Sims 3 doesn't work in general

• Sims 3 - Uninstall
  This Game_Help:TS3_Uninstall^wiki link has the step-by-step instructions to guide you through uninstalling The Sims 3, and its packs (EP/SP).
  
  If you're reinstalling because you're reverting to an older patch, or just do not want to use the Launcher/EADM to patch, read this FAQ Game_Help:TS3_Patching^wiki once through before patching and then follow the guide.
  
  

Have you registered your games with EA? if so, you should be able to download the Base Game with EADM. At this point, it might be best if you uninstalled and reinstalled everything following the guides above to make sure you clean up all the leftovers before reinstalling.

Ok, thank you heaps. I will definitely check out those links, and I will definitely register my game with EA when I do reinstall. Just in case this nasty incident happens again. Thank you~