whenever I add new configuration and delete several body, why the body increase?
Welcome to the forum. It will be very difficult to help without seeing the file. Can you post it? See How can I attach a file to a forum post? for instructions if needed.
Thank you for reply. I mean the body on DesignTree. It becomed double sometime triple. this happen after I upgrade to Solidwork2018.
I'm afraid I still don't understand. If you aren't going to post the Part maybe you could post screenshots of the tree before and after the issue to show what you mean.
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