Recently I purchased a new laptop for myself and everything i have installed onto my new laptop (including sims 4) has gone smoothly. And then we get to the sims 3... First off I own all my games on disc but I downloaded them onto my new laptop through origin (because for some reason installing through cd wasn't updating my game past 1.62 but that's a whole other story and installing through origin seems to have fixed this). Unfortunately, this had its own problems, and i had to use the alder lake patch to allow me to launch the game at all, which solved that issue. Now this issue. i can launch the game perfectly fine but once i get to the main menu and i try to open a world (for reference i have absolutely no saves yet!) the loading bar fills instantly and i get this message : "a serious error has occurred while loading (town name). please restart the application". this happens with every town i try to load. My first step was to go to google and see if there was a solution, which there was. i have tried every single solution according to this wiki : http://simswiki.info/wiki.php?title...or_Has_Occurred and none have worked. So now i don't know what to do.

When using unlocker, it tells me that nothing is locked and the only actions available are, delete, move, and rename the file. I do have a temporary solution, but it is a pain in the ass and i want a permanent solution. For now i just have to restart my laptop and do the second solution from that wiki and i can get into a world and create a save, etc. but once i exit the game i have to redo all of that to be able to access the save or open a new world. So I would like to not have to keep doing that just to play the game.

i do have cc and mods but i've tested whether this happens without them and it still happens so I know its not my mods/cc that are causing this. I have no clue what to do to solve this and any suggestion will help. My specs are:

processor: 12th gen intel core i7 (2.70 GHz)
Ram: 32 GB of ram
OS: Windows 11
Graphics card: NVidia GeForce RTX 3070 Ti
64 bit processor and OS

I get this error when I have the user folder opened while loading the game. So I close all file explorer windows before starting the game. Could this be the case for you too?

I also do that but it doesn't seem to help. but thanks anyways

Ok I have since done this and used the super patch to update to 1.67. First time loading in, it worked. So then i went and added some of my mods to see if it would still work. nope. Same error message. i even made sure all my mods were compatible with 1.67.
Since then i have removed all my mods to see if it was them that caused this but now it still is giving me the error message. So i'm not sure if it is the mods or something else causing this. I also made sure none of my user files were open too.

Edit: i tested it by restarting my laptop and then loading into game (which works) but then trying to load in after quitting to desktop and not restarting (and i hadn't put any mods in either) still gives the error message, even with installing via disc.
A friend suggested that i just use my old laptop just to play sims 3 (and uninstall everything else) which is the only game that isn't working on this new one so i'll probably end up just doing that if i want to play sims 3. sucks that i can't play sims 3 on this laptop i guess but oh well

In addition to maybe anti-virus, is it possible that OneDrive is locking up these files after a while and trying to do some kind of synchronization? OneDrive should not be used to sync the live (being used) TS3 user game folder and it tends to be on by default unless the user uninstalls it or switches it off on new Win 10/11 installs.

Thank you! I tried all of this. Disabling one drive fixed the problem! I also made sure to allow sims 3 through windows defender firewall. Thank you very much!