hfss error: unable to recover surface triangles

hi,
i would like to know the reasons for which the error "unable to recover surface triangles occur" in hfss v9. i get this error very often in my microwave filter designs. i use VB scripts to draw my design. please help.

thanks

I used to have a similar problem in CST. It was the mechannical
drawing(.sat files) where the surface intercept to each other.

the problem was sorted out. it was in the heavy meshing at the edges as i was using copper instead of the perfect conductor. so i changed to pec and the meshes worked out properly and gave me results

Hi

Even when I am using arcs in HFSS and designer , I face similar kind of problem. Though it doesnt give error many times, it takes ages to simulate.

This might be due to an error in the design. I have handled complex designs in ansoft

Most likely HFSS can't build mesh properly around your object. there are some object that are too small and complex to build the tet around. try avoid sharp narrow egdes which at time won't contribute too much to end result.

HFSS v10 has healing feature which can eliminate this problem