Paul Larsen
Ansys Employee

Hi Muhammad,  Check if this error occurs without the motion setup.  The motion setup in Maxwell 3D requires a solid object (can be vacuum) without holes to contain all the moving parts.  It looks like you have some coils that move in the x-direction.  I suggest that you draw a long ring with a cap on one end (so that it's one continuous object without holes containing the moving coil) that will move in the direction of motion within the band.  If this is not possible or too complicated, then you can always switch the moving/stationary assignment, and keep the coil stationary, but you need to keep the requirement that all moving objects are contained within a solid (vacuum) object without holes.