AutoCAD 2010 :: 2011 Crashes Upon Trying To Insert 3D Block

I created a number of 3D blocks to be inserted into a 3D model of a building.  I created the blocks in a separate drawing first; i defined them locally, then, when i had them the way i wanted them, I used "wblock" to save all of these blocks to a folder.

I then opened the 3D building model and tried to insert one of my new blocks.  I repeatedly get the following:

"AutoCAD Application has stopped working"

with the following info from microsoft:

"Description:
  Stopped working

Problem signature:
  Problem Event Name:    APPCRASH
  Application Name:    acad.exe
  Application Version:    24.1.208.0
  Application Timestamp:    4dbf9c16
  Fault Module Name:    KERNELBASE.dll
  Fault Module Version:    6.1.7601.17651
  Fault Module Timestamp:    4e21213c
  Exception     e053534f
  Exception Offset:    000000000000cacd
  OS Version:    6.1.7601.2.1.0.256.48
  Locale ID:    1033"

I have tried repairing my installation of autocad with no improvement.

i tried opening the drawing of the block itself, copying it, and pasting it via the "copybase" command into the other drawing with the same result.

Occasionally, autocad will ask me if i'd like to debug the program (and visual studio opens) -- it mentions a "StackOverflowException" within acad.exe, and also mentioned "windowsbase.dll".

I am using windows 7 pro x64 and autocad 2011.

CPU: intel i7

Graphics: NVidia GeForce GTS 250

8GB DDR3 ram

The autocad error-reporting dialog never gets launched as it is forced to close before this point.