在Windows7 ,安装step7 microwin 4.0 sp9 报错,提示crc error;the file c:/program/siemens/step 7-microwin v4.0/readmec.doc doesn't match the file in the setup's.cab file, the medium from which you are running the setup may be corrupted; contact your software vendor. 在xp系统下,安装microwin sp3,也是这样的提示,系统都是才新装的,求解,在线等谢谢