** ERROR 200180 ** One or more unconnected cavities are underconstrained. Check the constraints on the model and run the analysis again.
The solver has determined that one or more of your cavities is underconstrained. A warpage or stress analysis requires that suitable constraints be applied to the model to prevent rigid-body movement in response to the applied loads.
If you have more than one cavity modeled, you must manually constrain each cavity.
Check that you have applied constraints to each cavity in the model.