complex geometry

Hi
This is similar to question posted on 1/12/2007. I am exportingcomplex geometry out of solidworks and saving them asIGES/STEP/ACIS. However, when I reopen the IGES/STEP/ACIS fileswith solidworks, I get an error: No solid data in file. I am tryingto find out whether the complexity of the geometry is the problem.The IGES/ACIS and STEP formats are easier to import into othersoftware that I am using.SolidworksImport export