Since the release of Seasons, I've noticed a couple of threads where people are complaining of Game Crashing. This doesn't just apply to those people, however - it applies to everyone noticing crashes.
After you've gone through the regular steps, such as
What to do if your Game slows down (Clean up your game) and
Factory Reset: Fix your game with 1/4 the Time of a Reinstall, here is what you do.
First of all - is the crashing one off, or regular? If it's regular, consider investing some bandwidth and downloading this
Crash Log Analyzer (Windows Only). If you have an abundance of Mods/CC (as I do), now might be the time to look into
Delphy's Dashboard. The former requires .NET version 4.0 (minimum) on Windows. The latter requires .NET 2.0 (minimum) on Windows. Unsure of your .NET version? Navigate to C:\Windows\Microsoft.NET\Framework - there are subfolders entitled v3.0, v3.5 etc. The latest one (eg v4.0.30319) is your .NET version. Most Modern computers
should automatically be running 4.0.
Next up - scan your The Sims 3 Folder. To do this, launch the Crash Log Analyzer (you may need to select "Run" from a popup in order to run it). To put it nice and simply - it will go into your The Sims 3 folder and take a peek inside those .mdmp files (see
What are .mdmp's?) to try and determine what caused your crash. Of course, if you're like me and prefer to separate your .mdmp files from the rest of the game, you can set it to scan another folder once (the folder is not saved). To do this, go to the File menu and select "Change Log Directory to Scan..." and navigate to whatever folder contains your .mdmp files.
Right, now that's done, it should tell you what on earth your problem is. For instance, with one of my recent crashes, as FlynnArrowstarr stated to me via email, I needed to update my Graphics Card. If it doesn't, there are buttons at the bottom directing you to helpful links on MTS' wiki. You can also export the information found into a text file, or Copy it to the Clipboard.
For Mac users - I'm afraid there aren't a lot of possible solutions short of uploading your .mdmp's in .zip archives to this thread, where a Windows user with the Analyzer can scan it for you.
What are .mdmp's?.mdmp files, commonly called by their full name -
mini
du
mp files - contain general information about your Computer, and information regarding the crash in a usually human-unreadable format - for instance, the .txt files that accompany each one in TS3 don't explain much on their own.
So, if you're experiencing regular crashing, I hope this thread helps you.
Good Luck, and Happy Simming.
I would also recommend checking out this post. 
