I am able to use certain mods. However, I am trying to use mods that Dramatic-Gamer made for The Sims 3 unsuccessfully. When I get the game to load, I get a Mod Scripts Found message on the main menu before I play with my Sim character. Now, it is becoming nauseating to try to successfully overcome this weird mod usage limitation. Also, I need help on some other mods from different sources other than ModTheSims.

Mods don't need to be showing on that Script Mods Found screen at startup in order for them to function. The screen is only capable of showing a finite number of them, tuning mods will never show up there, but that doesn't stop them from loading at all. Are the mods in question truly not functioning in-game? Have you tried clearing (deleting) your scriptCache.package file from your TS3 user game folder in Documents?

Just to add to igazor's post: When you say "Mods" you are referring to files that change how you play the game and not Custom Content which is objects for build/buy, Create A Sim, etc. correct?

For help with other mods that are not here at MTS: The best place to get help is at the site(s) where you downloaded the mods. What mods are you referring to that do not function?

By the way, I have installed and uninstalled my game 2 times with no success. Yes, the certain mods are not functioning in the game. What happens when the scriptCache.package file is in my Documents folder? What happens when the scriptCache.package file is not in my Documents folder? Sorry, I am not new to adding mods on my Sims games. But, it seems like I need more explaining on how to use mods.

The mods I am trying to use are from Dramatic-Gamer who uploaded his The Sims 3 mods on ModTheSims.com.

The following files should be deleted from your user TS3 game folder in Documents whenever the contents of Mods\Packages changes in any way and periodically for routine maintenance at other times. Many of us do this before before every startup (or after every Quit, same thing). They are cache files and will get clogged with outdated information otherwise. They will all regenerate the next time the game is launched.

CasPartCache.package
compositorCache.package
scriptCache.package (this is the important one with respect to script mods)
simCompositorCache.package
socialCache.package (this one is optional)

Uninstalling and reinstalling the game is awfully extreme. It's your game folder in Documents that dictate how or if mods work, not the game install. If mods that we know should be working refuse to do so, perhaps consider taking the entire game folder out to force the creation of a new one that has no content and start over building it back up again. A reinstall does not accomplish this, that only affects what is in Program Files.

I had some of Dramatic-Gamer's mods in my game, and they were working fairly well. I took them back out because I realized that I wasn't really doing much with them, but the mods themselves were working.

(Note: He also has mods for Sims 4, which will not work in a Sims 3 game. I hope you weren't trying to use any of those.)

I will try that and see what happens.

Now, I get a message that entails this:

"Unable to start game

Your The Sims 3 Base Game is incompatible with the current Sims 3 Expansion Pack. Please update your game via the game launcher."

Do I update my game with that game launcher it is talking about?

What kind of an installation was this?

If it was all retail store disc and Origin was not involved with managing things in any way and you are intending to be on Patch 1.67, then I would suggest running EA's SuperPatcher. It's a huge download, but remarkably effective. The Launcher on its own does a pretty poor job of patching.
https://help.ea.com/en-tr/help/the-...3-super-patcher

If this was an Origin assisted install and you are intending to be on Patch 1.69, so that you must start up the game by way of Origin each time, then Origin is supposed to take care of these things automatically and you can't use the SuperPatcher. You might now have a broken install if you didn't clean the Registry in between uninstalling and reinstalling (assuming you are on Windows and not Mac). Perhaps let the Launcher do whatever it is trying to do if that makes the game happier.

Or is your game from and managed by Steam or from some other source?

The presence and clearing (or not) of cache files has nothing to do with patch levels.

I will try Origin to see if things will work from it updating whatever needs to be updated. I still want to use mods and wish Origin does not remove that opportunity. I am using a Windows computer with a downloadable install without the use of Steam, CD, or external storage device. How do I clean the registry in between uninstalling and installing the game?

Origin itself doesn't have anything to do with the ability to use mods. My install is all Origin as are those of many other players. Something else is wrong here, though we haven't identified it yet. I don't mean this to be insulting or disrespectful in any way, but if this "downloadable install" is from less than legitimate sources, then you will find that many mods will probably not work with it.

Most commonly used tool for Registry cleans is Piriform's CCleaner (the free version).
https://www.piriform.com/ccleaner

Sigh... the mods worked with The Sims 3 game I installed before I downloaded a certain mod on it that screwed it up. So, it was legitimate enough. But, the game wouldn't work anymore. So, I uninstalled it, thinking I uninstalled EVERYTHING. Apparently not, I guess. I installed it again and created the Mods folder and everything to find myself unable to use the mods yet still having them in their proper folder while the game would not crash. So, I came here to find someone like you. However, I am still not getting my problem solved even though I cleared the Registry on CCleaner, have the proper folders, have the right files to play the game, and I still CANNOT use certain mods. Also, I did delete those 4 files again after recreating The Sims 3 folder in my Documents folder and started the game again without that Unable to start game message. Still, I am unable to use Dramatic-Gamer's The Sims 3 mods.