I am not sure if the above comments are directed to me or not. If so, I do NOT have any X versions of Chiefarc. My Chief 8 full was an upgrade from 7 full and was purchased on Feb 2, 2003. The point is almost moot at this time. Working on a packet for permit and construction purposes. Part of that is a structural cross section which is time consuming to draw. I am almost done with that layer now so my immediate need has disappeared. I am still curious as to why it appears my older files may be opened using a version at least 10 newer, yet I can't open files that are 2 versions back. IE use Chief 8 to open chief 7 or 97.
History: My purchased versions starting in 1994 with 1.2, 2.0, 3.0, 4.0. Those were all shipped on 3 1/2 floppies. There were MANY updates to all those prior releases. Then 1997 was released 8/7/97, 6.0 on 7/18/99, 7 unknown, 8 bought on 2/2/2003. Those were all on CD. That was the extent of my purchases.