Model Unit System = None

Rhino.Inside Revit
1

When importing .3dm file into revit, it shows error

Model ‘Untitled.3dm’ has an unsupported model unit system. Model Unit System = None.

Revit 2025, RIR 1.31, Rhino 8.18

Untitled.zip (709.1 KB)

2

If the untitled.3dm file you posted is the original file from Rhino then it has indeed been created without units.

image
image1560×450 26.9 KB

In Rhino, go to Tools>Options...>Units and change the units to what they should be.

HTH
Jeremy