Sims 3 "Unofficial game modification" error. [SOLVED]

I know this has been posted a million times but please hear me out!
Yesterday I was playing The Sims 3 with absolutely no problems.
Being unaware that I was not supposed to update to 1.31, I did just that.
After realizing it was a mistake, I launched a System Restore, rewinding to a few hours earlier, before I applied the update.

So now I'm back with 1.29 but the game will no longer launch. I have tried applying the latest fix over and over.
Every time I try to launch the game I get the "Unofficial game modification" error & when I press "continue" it crashes after 3 or so minutes after being on the "Master Suite" loading screen. I have no custom content & no mods. Every post I've seen related to this issue has recommended to apply the latest fix, which is all I've been doing. I'm stuck!

Hello,

I'd indeed recommend waiting for the Fix' update. When it has been updated, download the v1.31 (NOT the v1.29 one!) manual patch from here: https://games4theworld.forumotion.com/t1870-can-t-update-the-sims-3-to-v129-fix-manual-patch and then re-download and re-apply the latest version of the Fix.

Thanks you guys. I didn't consider that it didn't completely get rid of 1.31. I'll wait for the latest fix.

Hello,

Good! Can I close this topic for now?

Actually, one quick question! (Sorry!)
Depending on how long it might take to wait for the new 1.31 fix, I might want to try reinstalling. The question is, would I have to reinstall everything? The base game AND expansions? Or would I just have to reinstall the base game?

Hello,

As far as I know, yes, you'll have to reinstall everything, restart your PC and then reinstall everything.
After re-installation, you'll need use the version 1.29 manual patch.

I'm better off waiting for the newest patch then. Thanks for your help! You can close the topic if you wish.