微带滤波器用HFSS仿真时出现错误

 

HFSS完全新手， 我要仿一个低通微带滤波器，模型如上，在HFSS上运行后出现错误，错误提示如下：
 HFSSDesign1
    [error] Initial mesh, process mesh3d : Error while opening or writing the mesh files. (3:16 下午  五月 28, 2009)
    [error] Simulation completed with execution error on server: Local Machine. (3:16 下午  五月 28, 2009)
    [error] Mesh generation has failed. Specific details may be found in 3D Modeler>Model Analysis>Show Analysis Dialog>Last Simulation Mesh. (3:17 下午  五月 28, 2009)
    [error] Simulation completed with execution error on server: Local Machine. (3:17 下午  五月 28, 2009)
 
大虾们帮帮我吧，可怜的我时间不多了
 感激不尽啊