I am using autocad architectural desktop release 3 with the operating system windows 7. When Attempting to open a file I get the following error:
FATAL ERROR: Attempt to delete class 'AecDatabaseData' which still has registered descendants.
10/15/2012 at 10:13:47.292 Drawing: R:\Everyone\Plans - Year 37\SITE PLAN XXXX\Site plan XXXX.dwg
Anyone have any idea how to correct this? I cannot open up any of my files. The sample drawings in autocad open up just fine. Thanks in advance.