Re: There are no sims anywhere
Just to be sure, do you have any sims other than the household you are playing in Manage Households? I am assuming there are, based on what you've said, and they just aren't wandering around in the worlds or showing up.
So, since you use mods, it is likely that you've got a mod that's causing it. You said you turned off, but how did you do that? Did you just uncheck the boxes in Gameplay Options or did you move or delete the mods from the Mods folder?
If you just unchecked the boxes and didn't move the mods out of the game path, then that may be part of the problem. What you need to do is move your mods folder to your desktop and delete the localthumbcache.package file. Then start the game. Go to a household and watch to see if any sims outside your household show up anywhere in the zone you're in. When you are done, just exit, don't save while you are testing since your CC isn't present.
If sims do show up while you test, then you need to go through your mods folder and find the mod or mods that are causing it. CC generally doesn't cause issues like this so I would test that last. Chances are that it is a mod. Once you find the mod causing it, you should either remove it or check wherever you got it for an update and replace it with the newer version. Don't stop testing until you have been through all your mods to make sure that other mods you have also cause the problem.
Hope this helps.