@sandyb561 Does your computer run Windows or macOS? I can move your post to the relevant Sims 3 section. And do you get any error messages when you try to play TS3? A screenshot would be helpful; you can attach it directly to a post.
I ended up uninstalling Sim3 and reinstalling but it still wont launch. I don't get any error messages. I click on it and the screen will blink once and then nothing. all of the other games on origin run great its just TS3. oh by the way thank you, and yes go ahead and put it on the relevant TS3. I have Windows 10. I don't know how to do a screenshot.
@sandyb561 Please check to see whether .NET Framework 3.5 is enabled on your system; it isn't always on by default in Windows 10. Hit Windows key-R and enter "appwiz.cpl" (without quotes) into the box. In the File Explorer window that shows up, click "Turn Windows features on or off," and you should see this:
You should see .NET Framework 3.5 right at the top, shown in blue inside the first red box above. The box next to it should be filled in just like in this screenshot.
If this isn't the issue, try launching Sims 3 while completely offline, i.e. turn off wifi and/or pull the ethernet cable. If you play through Origin, sign in first and then put Origin into offline mode.
If that doesn't help either, please run a dxdiag and attach the results to a post here. It will provide information on a lot of potential issues all at once.
P.S. To take a screenshot, hit Windows key-shift-S and drag your cursor over the section of screen you want to capture. Then open Paint or another image editing app, and ctrl-V to paste the screenshot you just took.