I got a bit of a fright a couple of days ago when my game started crashing on launch. Just before that, I’d installed some horses, which had come up clean in custard, but were still the most obvious culprits. I tried removing the horses via the launcher but the uninstaller just kept crashing before it could do anything, and I tried deleting them from my saved sims file but the crashes persisted.
I poked around my game files a bit, and by process of elimination discovered that something in my dccache folder was to blame (which, incidentally, was also the case the last time I had major crash-on-launch issues). As I was contemplating the mind-numbing possibility of having to reinstall all my store content, I remembered I had a clean dccache backup I’d taken a couple of years ago. The old folder worked a charm, and my game is now working again.
So the moral of the story is back up all your files, but especially that oh-so-delicate dccache, because the launcher will break it at some point.