Hi guys I used the class itkVTKPolyDataWriter in Review directory to write my meshes as vtkPolyData but when I try to read them using vtkPolyDataReader I get the following error, I checked the file and it seemed to have the format of vtkPolyData >>> a = vtkPolyDataReader() >>> a.SetFileName("MESH5.vtk") >>> a.Update() ERROR: In /build/buildd/vtk-5.0.3/IO/vtkDataReader.cxx, line 1631 vtkPolyDataReader (0x95c650): Error reading ascii cell data! for file: MESH5.vtk any ideas Leila