Can't setup sims 3 base game

Hello! So my problem is that I downloaded the complete collection of Sims 3. I installed the base game correctly, then seasons, pets and uni life. After downloading university life package, the game did not start anymore, as it was saying "Insert the disc". So... I deleted all files that were connected to the sims 3 and expansion packs. Now i tried to download the base game again, but it keeps saying the following on setup: 

"The setup has detected that version 1.67.002 of the Sims 3 is already installed. This setup installs an earlier version of The Sims 3 (1.0.615). You will have to uninstall the previous version before installing this version". 

The problem is that I already uninstalled it! So, maybe somebody can help me figure out this mess and how I could actually get to playing the game  

Thanks!

You probably uninstalled it by simply removing the files/folders.
This means that - according to the register - your old installations still exist.
Delete the register entries with f.e. a program like Revo Uninstaller.
Or do it manually:
1. Keep Windowskey pressed down and type R
2. In the window type regedit and click on OK
3. In the register open HKEY_LOCAL_MACHINE
4. Open SOFTWARE
5. In 64-bits Windows open WOW6432Nodes
6. Open the folder Sims
7. Delete all Sims 3 related folders.


Reason why the game did not start and asked for the correct disc is that you tried to start the game via the shortcut of Seasons instead of University.

EDIT:
Also remove the Sims 3 related folder in the register-entries under
HOTKEY_LOCAL_Machine ->SOFTWARE ->WOW6432 Node->Electronic Arts->Sims