Endless Saving

@keelyfern  It sounds like there are two main possibilities here.  First is that your game is borked.  The presence of NRaas mods makes this less likely, but still possible.  Hopefully, you have ErrorTrap, Overwatch, and MasterController already in place; if not, now's a good time to add them.  You might try a MasterController reset of the entire town as soon as you load up your game—click on City Hall, NRaas > MC > Town Options > Reset Everything.  It might take a few minutes to complete, but if you watch in Map View, you should be able to see sims being reset back home as the command runs.

If this doesn't help, you can try all of the above on the backup copy of your save.  Even if you never make backups yourself, the game keeps a copy of the file from the second-to-last time you saved.  Hopefully, this isn't corrupted too, or at least is less so.  In your Saves folder, you can find that save, remove the .backup extension and rename it, and then it will appear as an option at the Main Menu like your other saves.

The other possibility is that your save is using almost all of the RAM available to it just on startup, and even a few minutes of gameplay pushes it over the edge.  That would explain why you can save right at the beginning of a play session but not later on.  You can check RAM use in the Task Manager—put the game in windowed mode, open TM, and watch what happens as you try to save.  If you're seeing percentages of memory use, right-click on the category heading to switch to absolute numbers.  TS3 is a 32-bit application and can therefore use only 4 GB RAM at a time, but the danger zone is anything above 3.7 GB.  If your save is consistently near this limit, then you'll probably need to pack up your active family and move them somewhere else.

If none of this helps, please run a dxdiag and attach the results here (use the Browse button).  Please also list the packs you have installed, the world you're playing in, and which mods you're using.

https://answers.ea.com/t5/The-Sims-3/HOW-TO-DxDiag-PC-Only/m-p/1049584/thread-id/47181

@puzzlezaddict Thanks a bunch for your response!! I actually did not have those NRaas mods, only the auto-saver, and story progression ones. I installed them and did the reset everything command, which seemed to fix it at first. I ran my sims through a day and saved when they slept, which went fine. Directly after that, I did some things in buy mode, including using buydebug mode to get all of the possible toys for the toy chest. I saved after that, which did not work. Is it possible buydebug is breaking the save, as I think I've had it on every time..

@keelyfern  Buydebug itself probably isn't the issue, but spending time in Build/Buy could be.  It drives up memory use much faster than regular gameplay, as do Edit Town and CAS sessions.  StoryProgression also requires extra RAM to run, although you can fiddle with the settings to tamp that down a bit.

If you want to talk about ways to keep your RAM use down, it would be helpful to know the information I listed earlier.  Your system's specs will influence how much you can do; some worlds (and some packs) are more demanding than others; a couple of other NRaas mods may help as well, depending on which packs you're running.

Edit:  I forgot to add that you should definitely make copies of your main save and its backup before doing anything else, and place them somewhere safe.  From now on, you should also use "save as" instead of save and rename the save slightly each time.  That way, if a save fails, there's no chance of you overwriting an existing healthy save with a corrupt one.

@puzzlezaddict I've attached the text file of the DxDiag here! And yeah, I've got 2 save files for the particular game, and a full backup folder on my desktop, because the first time it happened, my main save file was deleted! Thank you again!

@keelyfern  Alright, you have enough RAM to run TS3, but it's not a good idea to have much more than a browser window or two open while you play.  (That 8 GB can get used up quickly.)  Your graphics card isn't really powerful enough to run the entire game on high settings, but again, that will depend on which packs you have installed and what world you're playing in.

It's also a good idea to check your in-game frame rates.  While an Nvidia 940 Mx isn't capable of throwing incredibly high rates like some of its more powerful cousins, you might still be getting fluctuations.  To see your frame rates, open the cheats console (crtl-shift-c) and enter "fps on" without the quotes, and a number will appear in the upper right corner of your screen.  Keep an eye on that number as you move the camera around and let me know how it behaves.  (To turn it off again, enter "fps off.")

Please also keep the Task Manager open, at least once with this current game, and tell me what kind of RAM use you're seeing.  There are ways to lower memory use, and there are ways to troubleshoot if RAM isn't the issue, but there's not a lot of overlap between the two categories.

And again, please list the packs you have installed and the world you're currently playing in.  You might not think it makes a difference, and you could be right, but there might also be an obvious issue that can be solved without jumping through all the other hoops.

Last thing:  Please copy and paste the first 40 or so lines of your deviceconfig here.  You can edit out your username (around 25 lines down), but include everything else until you get to the game options.  This shows what TS3 thinks of your hardware, and specifically whether it's using the dedicated or integrated graphics card.

I know this is a lot of information, but the more you provide, the easier it is to start crossing potential issues off the list and find the ones that need to be addressed.

@puzzlezaddict

Sorry for missing things out so much!

For starters the stuff/expansion packs I am using are:

Generations

High-End Loft Stuff

Late Night

Outdoor Living Stuff

Seasons

Town Life Stuff

University Life

And I am currently playing in Bridgeport

My current memory usage from the sims while running the game sits around 1,270-1,280 MB

As far as the fps goes, it sits between 50 and 80 mostly, both static and when moving the camera.

The graphics info section from deviceconfig is pasted below this.

OS is 64Bit: 1
CPU: GenuineIntel
Brand: Intel(R) Core(TM) i7-6500U CPU @ 2.50GHz
Family: 6
Model: 14
Cores: 2
HT: 1
x64: 0
Memory: 8056MB
Free memory: 3172MB
User: New User
Computer: XXXXX
=== Graphics device info ===
Number: 0
Name (driver): NVIDIA GeForce 940MX
Name (database): NVIDIA GeForce 940MX [Found: 0, Matched: 0]
Vendor: NVIDIA
Chipset: Vendor: 10de, Device: 134d, Board: 119e1043, Chipset: 00a2
Driver: nvd3dum.dll, Version: 21.21.13.6909, GUID: D7B71E3E-500D-11CF-0E69-933118C2D835
Driver version: 6909
Monitor: \\.\DISPLAY1
Texture memory: 32MB <<OVERRIDE>>
Vertex program: 3.0
Pixel program: 3.0
Hardware TnL: 1

Thank you again for all your help!

@keelyfern  One thing I see right away is that your computer is using up more than half its memory when you launch TS3.  Whatever is running in the background, try to keep it at a minimum.  This alone could account for your crashes, especially if the other app(s) start demanding more memory while you play, and meanwhile you're in Build/Buy, or there's an in-game glitch demanding more resources of the game engine.

But that may not be the immediate cause of your crashing.  Is it currently snowing in your game?  Snow and hail are particularly hard to render, and your processor and graphics cards are a bit weak for TS3's most demanding packs: Pets, Seasons, ITF, and IP.  Seasons alone should probably be okay, and the rest of the packs you own aren't nearly as demanding (though adding any more of the heavy packs might cause your system more stress than it can handle).  But if you only get crashes during inclement weather, you might need to disable it or turn down your graphics settings during winter.

Another thing that might take some of the stress off your graphics card is capping your in-game fps.  You can try the built-in Nvidia Control Panel, which doesn't always work, and never works in windowed mode, or Nvidia Inspector (free download).  Either way, keeping your fps at 60 will be better for your card and possibly help with the crashing.  Here are screenshots of the setups for both tools, under the spoilers:

https://forums.thesims.com/en_US/discussion/comment/16540301/#Comment_16540301

You also need to update your graphics card drivers.  You should be able to do so from your computer manufacturer's website (Asus), or failing that, Nvidia's site.

Bridgeport is a bit problematic, due to the way the NPC areas of the apartment buildings are made.  The MasterController Reset Everything helps temporarily but won't solve the issues entirely.  ErrorTrap and Overwatch help too.  In the future, you might look into Ellacharm3d's fixed Bridgeport, or you can try some of the edits yourself, if you're good at that kind of thing (I'm not).

http://modthesims.info/d/452601

There are still probably a few more things you can try, if none of this helps, but it seems like a good place to start.