A Serious Error Occurred

@xQueenxJx  How did you go about creating a new Meta.data file, and what did you do with it?  The set of issues a new copy would fix is very narrow, so I'm not surprised it didn't help.  Additionally, there's no reason you need to put a .bad extension on a save; you can just move it elsewhere or rename the backup instead.

As an experiment, please try loading the backup save in a clean user folder.  Move the entire Sims 3 folder out of Documents > Electronic Arts and onto your desktop, and open the launcher to create a clean folder.  Create a Saves folder inside, and copy and paste just the former backup save into it, but don't add any other files to the new folder.  Launch the game and see whether you can load the save.  You won't have your mods or cc available, but that's part of the point.  Just let me know whether it works.

@puzzlezaddict I created a new Meta.data file by making a new save file a couple days ago (while my messed up saves were still there). I put a copy of it in each .sims3 folder. Doing so brought me from "Cannot load this save game. It may have been saved with expansion pack data that is no longer present on this system." to "A serious error has occurred while loading '[savename].sims3'. It is strongly recommended that you restart the application." once I was able to select my save file. Two things to note: 1: the new save that I got the new Meta.data from showed CC in build mode and NRaas on city hall so the mods and CC were working; 2: on the main menu, any old save with the new Meta.data in it will show the name when the cursor is over it, not have a photo (neither fam or house), and the description and title will be of the family I created the Meta.data file with rather than the actual save's family.

I tried loading the backup in a new user folder but it said the whole thing about how it might've been saved with expansion data that's no longer there so it can't load. Because of that I tried the Meta.data thing which brought up the "serious error" box. At that point I decided to look in the new save folder that I got the Meta.data from and noticed another file named "1a5tf1l3.dat", so I put that into the save file I had put in the new user folder and it worked! The game loaded and everything. The only thing is I think that's the one family I didn't use CC or mods with yet. However after a couple of minutes of looking around on pause, I went to the family's penthouse, went up a level, and the screen turned red. It literally pulsated red like a strobe light 😭 I panicked but was able to go to map, so then I went back to the penthouse and it was on the floor I was trying to go to, which has a red room in it. I think that was where the red came from. I changed levels again and it went red again, and then it froze so I force quit the game.

I tried to load a different family that uses CC and mods and it would start loading but not finish. I tried a few times. It always seemed like it was gonna work because the bar would start filling and I could play with the loading screen, but it never reached halfway and would just stop. The music would still play though. Maybe if I wait for 20+ minutes it'll load 💀😭 I did that before, like 2 years ago.

Any ideas? I'm stumped. (sorry this is so long lol)

@xQueenxJx  The Meta.data file contains the thumbnail and info you see on the save screen, so replacing the file with one from a different save is supposed to have the effect you've described.  If you can load the save, you've accomplished what you needed to, and when you next save your progress, the info from the correct household should be saved as well.

The red pulsing is a known issue with the 64-bit version of Sims 3:

https://answers.ea.com/t5/Technical-Issues-Mac/CURRENT-ISSUE-64-bit-red-flashing-game-window/m-p/9664938#M12080

Feel free to click Me Too and post in that thread if you want.  However, there's no known fix other than to not play affected lots.  You could instead try to redesign the penthouse and see if you can remove or replace enough objects to avoid the problem; zooming out or in far enough may get rid of the flashing and allow you to work.

I tried all of theses solutions and none worked but then I found a comment on a youtube video, it was One Drive all along,  A serious error has occurred while loading 'Sunset Valley.world'. youtube comment quote "...solution: I disabled OneDrive, then renamed folder

C:\Users\XXX\OneDrive\Documents\Electronic Arts\The Sims 3

to

C:\Users\XXX\OneDrive\Documents\Electronic Arts\The Sims 3 Old

Game regenerated folder, than i enter into the world. Then copy everything i had in old folder

And then Sims 3 actually loads worlds"

Hey there,

This thread is quite old and is being locked here to make sure info provided or reported is relevant to the current version of the game.

Feel free to create a new thread if there's a subject you're wanting to discuss that doesn't have a more recent topic, though in this case our ongoing thread here would be more suitable. Thanks!