When I added Jaguar to my iMac G4, I was told it was a stand-alone program and that I should erase the harddrive first. I did that, and once Jaguar was running, it no longer ran Classic programs. So, then I started over with the original System X software, then added Jaguar, and the classic programs ran again. That also worked on my Ruby G3, but not on my blue and white G3. I should have come here first, but live and learn. So, can someone please tell me the correct way to upgrade the system, and not lose the capacity to use System 9 programs? Also, I'd really like to add either Panther or Tiger, (when Tiger is available), but I want to know the right way to do it. Thanks!