Sims 3 installation problems. due to latest orign update

@StrangeAngels  Now that the driver situation is squared away, try another clean uninstall of Origin.  Clear its cache first:

https://help.ea.com/en-us/help/faq/clear-cache-to-fix-problems-with-your-games/

Then use Revo Uninstaller (the free version is fine, either regular or portable) to remove all traces of Origin, except for the Origin Games folder.  Here's how:

• Quit Origin, then right-click on the Task Bar and open the Task Manager.  Scroll through looking for Origin entries.  If you find any, click on them and End Task.
• Download Revo Uninstaller from here (again, the free versions are fine).
• Install Revo, open it, and uninstall Origin.  When it's finished, Revo will ask you which cleaning method you want to use.  Select "Moderate" and then Browse.
• If Revo finds any remaining registry entries, select all, delete, and click Next.
• Revo will display "Remaining Data and Folders.  Select all of them except for the "Origin Games" folder.  (This is where TS3 and other Origin games are located.)  Delete the rest.
• Restart your computer.

Next, download and install Origin—the regular version, not the beta.  Here's the direct download link:

http://download.dm.origin.com/origin/live/OriginSetup.exe

Be sure to run both the ThinSetup (the installer) and Origin itself as an admin: right-click on each and select "Run as Administrator."  Let me know how it goes.

(Thank you @holger1405, as always; you're wonderful.)