将igs文件导入LT出现以下问题: <;yS&8
5|~nX8>
*** Error (AITX_BLANKED_ENTS) *** d"IZt;s/,
kI9I{ &J&
The input file did not contain any supported non blanked independant entities. zc=G4F01
by0K:*C
Please check the documentation for a list of supported entities. :4-,Ru1C"
.%)uCLZr$
请教各位是什么原因,如何解决?