Re: Sims 3 login
@sweetteabirdie Try moving your existing Sims 3 folder out of Documents\Electronic Arts and onto your desktop, which will let the game generate a new folder when you open the launcher. (Your saves and other content will be intact in the folder you've moved but temporarily not read by the game; we can address that later.) Don't add anything to the new folder; just try downloading an item from the store website and see whether you're asked to sign into the launcher.
If this doesn't help, please let me know what kind of install this is: Origin, disc, Steam, a mix of disc and Origin, or something else. Please also let me know whether you have two EA/Origin accounts, especially if your Sims 3 content—packs or store stuff—is divided across the accounts.