HFSS mesh3d internal error: need help

I got an unusual error message in HFSS when attempting to run a solution (even after I had run validation successfully):


[error] Initial mesh, process mesh3d : Unexpected internal software error code -1073741819 with module id 0. (4:37:43 PM Jun 12, 2014)
[error] Simulation completed with execution error on server: Local Machine. (4:37:43 PM Jun 12, 2014)

All of the shapes in my structure are rectangles, except for one, which has a hole in it (but the hole is rectangle shaped).
I don't understand how such a simple structure leads to a mesh error.
I can send the file if you want to see it.

Thank you for your help!