Re: sims 3 base game wont install
@katsimming It might be your antivirus/firewall blocking the game from launching, or from writing to the Documents folder. Try disabling it temporarily, just long enough to test. If the game launches, you can set exceptions for Origin.exe and TS3.exe.
And make sure Windows Defender's Controlled Folder Access isn't blocking the game either. The same idea applies: if Controlled Folder Access is enabled, set exceptions for Origin.exe and TS3.exe. This post is for Sims 4, but it's the same process:
https://crinrict.com/blog/2019/03/windows-10-defender-controlled-folder-access.html
Before you do anything else, go into Documents\Electronic Arts and remove your Sims 3 game folder, if you have one. If the permissions on that folder are messed up, the easiest way to fix it is to spawn a new folder, which the game will do the next time it loads.