I have an older ver of Inventor (ver 5) and I downloaded Inventor LT to try and I have created some parts with it and I have had files e-mailed to me that are newer versions of SolidWorks as well.  Now the only way I can view the files is to save them as a .stp file, but I can't do much with it as far as placing some constraints.  Is there a FREE conversion software that would allow me to save them as a lower ver of Inventor? Breeze1042007-10-31 21:27:38

No, you cannot save Inventor files to older Inventor formats (this limitation applies also to other 3D solid modelers). See also:
http://www.cadforum.cz/cadforum_en/qaID.asp?tip=4361

Thanks for the info.  
 
That is what I thought, but I hope that someone creates the software to be able to do that or creates an update for 3D modeling software that allows that;  Because this type of software is the only one I have ever used that wasn't that way.  Also, it would only make good sence because not everyone updates when ever new software versions come out.  Breeze1042007-11-01 13:23:23