To Import a 3DM File

Choose File > Import > 3D Modeling File Types > 3DM.
The Import dialog opens.
To change the filter, select "OpenNurbs (Rhino) File (*.3dm)" from the Files of type: list.
(Optional) To select a different source disk drive or directory, choose the desired drive or directory from the Look in list.
Select the desired .3dm file.
Click Options.
The OpenNurbs File Settings dialog opens.
Turn on the desired file settings and click OK.
Click Open.