Autodesk Architectural Desktop 2007 & Prior

[#1]

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.

Eddie

[#2]

Try using RECOVER command.

[#3]

Can the Recover function be used on a file that won't open?  If so, how is this accomplished?

Thanks

Eddie

[#4]

I tried to recover the file and I got the following message: Aecloader could not load requested module error Aecbase20.dbx.

Any ideas what is causing this?