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[diesel2370]

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[Theraven]

Delete the .cache files (accessory, groups, cigen and contentRegistry) from the "the sims 2"  folder in "my documents". That usually helps for me.
Those files regenerate every time you run the game or bodyshop, and often go borked...

If that doesn't help - try to move out whatever you've got in the SavedSims folder too. Might be a borked file from there.

[Theraven]

Could be that the SavedSims folder or the Downloads folder is somehow borked. You could try to move them entirely out, and let Bodyshop regenerate new folders. You could also try to move out the project folder (if there is one)

[Theraven]

The half'n'half method usually works. Split the contents in two, then test the one part. Borked? Then the file is there. Working? Then the file is in the other part. (test both parts, just to be sure). Then split the borked part again, and test. Do it until you've found the file.

I was messing around with some hairs, trying to bin them by hand. Somehow I managed to make hair show up on all the male bald heads, but didn't notice it until I was testing out some other hair. I should've figured it out it was the hair I had binned, but didn't think that far. So I messed around with the half'n'half method for an hour or so - until I finally narrowed it down to those hairs. I removed them, found out everything was back to normal, and then fixed the hairs.

[Engram]

The Saved Sims folder usually contains stuff you made. So it should be sims and any bodyshop content that you made, which should be easy to identify since YOU made it. Unless you've been putting other things in there.