Re: Sims 3 Launcher Won't Open - Error During Startup
@ladygreeneyes649 First of all, no one is going to tell you that Origin will fix your issues, or that you need an Origin install to troubleshoot. When the game itself works but the launcher does not, the issue is almost always in the Sims 3 user data folder (the one in Documents\Electronic Arts), not in the game's program files. So the fix would be limited to, at worst, uninstalling and reinstalling store and custom content. But you're not even at that point yet.
A few other notes: It sounds like Windows is set to not display file extensions, which is why you see, for example, TS3 and TS3W instead of TS3.exe and TS3W.exe. It's normal for the program files to have a number of executables, some of which are not used. The relevant point is that one of them opens the launcher, and one opens the game without needing the launcher; you can ignore the others.
It's usually not necessary to run the game or the launcher as an admin, nor to use a compatibility mode for either one. Personally, I'd undo the compatibility setting, at least to test. I understand that it used to work, but that's just an additional variable unnecessarily added to the mix. You can go back and forth if you want though.
It's also possible that the issue is in the cache for Internet Explorer, which the launcher uses for some purposes. Even though this is an uncommon cause of the launcher not opening at all (as opposed to opening but not loading), clearing IE's cache is simple. Be sure to uncheck the box to preserve data for favorite sites.
https://kb.wisc.edu/page.php?id=12313
The more likely issue though is that something corrupted in your user data folder. The fastest test is to move the entire Sims 3 folder out of Documents\Electronic Arts and onto your desktop. If the launcher opens (which will spawn a clean folder with no content), you know that the issue is one or more files in your old folder, and you can start adding them back to test.
Add the contents of DCCache first: it holds installed store and custom content, the most common source of these kinds of issues. If the launcher refuses to open again, you can test just the .ebc files (bundled store content), and just the .dbc files (bundled third-party custom content). If necessary, you can test the files one at a time, using Method by Mell on this page:
https://sims3.crinrict.com/en/2011/01/tutorial-how-to-get-rid-of-unwanted-custom-content.html
If a single bundle is the issue, you'd only need to reinstall the content of that bundle, not the rest.
To be clear, there are other files necessary to make some store and custom content load in-game: .world files in InstalledWorlds, .package files in Library, ccmerged.package for premium store content. But when trying to get the launcher to load in the first place, you can leave those until later.
If the files in DCCache aren't the issue, you can start testing your other contents of your user data folder. Here's a complete list of everything in that folder, along with explanations of what the files are and whether you'd need to preserve them:
https://sims3.crinrict.com/en/2011/01/faq-user-files.html
Finally, if you can't or don't want to figure out what the issue is with your user data folder, there are ways to install content into a clean folder and then combine it with your existing content. It can be a bit convoluted, depending on which content is involved, and it's certainly more annoying than fixing the launcher issue in the first place. But it's a reasonable alternative to consider. Let me know if you're interested, and what you're trying to install.