Hi, when trying to export a 3D file in Step format, I got this message:
![](https://uploads-us-west-2.insided.com/zemax-en/attachment/0c2d63a6-8031-4ffc-a77f-ebecdb58f011.png)
I looked on the web and found I should try to toggle “ Setup..Project Preferences..General..Use ACIS Libraries”, but in my version of zemax (the latest), no “project preference”, there is “optic studio preference”, under which I find nothing about ACIS libraries…
Thanks if anyone have an idea.
Julien