November
I know this thread is from years ago, but I’m also having this problem. I transferred from a PC playing 32 bit to a Mac playing 64 bit, and I transferred all my cc. I’ve never had a problem with any of my cc before, and it’s all the same from playing on my PC (meaning I haven’t downloaded anything new). But in all my worlds on my Mac the game would crash right after entering name and traits after birth, so I tried every solution I could find online except running the game without cc (because I didn’t want to replace everything afterwards). Yesterday I caved and replaced my Sims 3 folder with a fresh one in the EA folder, and I ran my world without any cc and I got past the birth and everything worked fine. I reinstalled my cc, but the game is still crashing after birth in my other worlds. I don’t want to have to uninstall and reinstall my cc every time a sim gives birth. My point is that I’ve never had a problem with my cc until using it on my Mac, so I don’t think any of it is bad, but the problem seems to be how the cc is received in the game during birth? Any thoughts on how to tackle this?
November
@Lollie432 You may have gotten lucky with your custom content in the past, or maybe there's an item that doesn't agree with the Mac version of Sims 3. Either way, you'll need to isolate the file and get rid of it. For .package files, use the 50/50 method. Test half your content, and if it's fine, add half of the rest. If you encounter the error again, remove half of what you just added. In this way, you can quickly whittle down a large number of files.
For launcher-installed cc, use Method by Mell on this page:
https://sims3.crinrict.com/en/2011/01/tutorial-how-to-get-rid-of-unwanted-custom-content.html
Only you'll be testing the .dbc files, to find out which file hosts the prolem item, before trying to remove that item.