Fatal Error when creating parts

[jnutt]

When I try to create parts I get a fatal error message.

1. in elevation view I select a wall

2. select 'create parts'

3. select 'divide parts'

4. select line to edit sketch

5. draw vertical line

6. select 'finish'

7.  I get a message "A fatal error has occurred. The application will be terminated etc"

I have shut down Revit & restarted my computer with no luck.  Any help is greatly appreciated!

Justin