https://forums.autodesk.com/t5/autocad-forum/trimming-intersecting-lines-locks-program/m-p/5516906#M339385 <P>&nbsp;</P> <P>Hello</P> <P>&nbsp;</P> <P>Welcome to the Autodesk/AutoCAD Forums ! </P> <P>&nbsp;</P> <P>1) Maybe you try to trim 2D or 3D objects (concrete-lines...) with 3D Objects (contour lines) !? </P> <P>TRIM is not really a 3D command !</P> <P>&nbsp;</P> <P>Is the command TRIM running well on PURE 2D objects on your PC ?</P> <P>&nbsp;</P> <P>2) An other quick idea : have you installed the SP2 on your ACAD 2015 ?&nbsp;</P> <P><A href="http://knowledge.autodesk.com/support/autocad/downloads/caas/downloads/content/autodesk-autocad-2015-service-pack-2.html?v=2015" target="_blank">http://knowledge.autodesk.com/support/autocad/downloads/caas/downloads/content/autodesk-autocad-2015-service-pack-2.html?v=2015</A></P> <P>&nbsp;</P> <P>&nbsp;</P> Mon, 23 Feb 2015 15:26:59 GMT braudpat 2015-02-23T15:26:59Z