Exxit - Not back-up. I mean can I save-as a 2008 file to a 2000 or 2004 DWG format? I know 2008 saves in 2007 format but I need to go to both 2000 and 2004 for customer applications. BTW - one of my customers' claim that accuracy is lost when you DXF file. Is this true? (Is it obvious that I'm not much of an AutoCad man? I primarily work with SolidWorks or SolidEdge - haven't used AutoCad since the 2000 days...) Thanks - Dadelar
loss of accuracy can occur in dxf's if the precision level is set low. All coordinates will be saved in ascii format with a fixed number of decimal places. If you work with very small numbers or very high tolerance dimensions in yor drawings, you could lose some accuracy.
You can control floating-point precision of the DXF format up to 16 decimal places. If that doesn't provide enough accuracy for your application, then dxf files will be less accurate.
Unless I am missing something, you should just be able to go to the "Tools" / "Options" menu and under the "Open and Save" tab select what AutoCAD version you want to save as.