When a verilog source file is added or removed from the ISE project,
the following Dr. Watson error occurs:
Exception: access violation (0xc0000005), Address (0x00416605)
The error also occurs any time the project is modified, and the
files are analysed. This causes problems as the file that generates
this error is not fully analysed.
This problem has been resolved in the 4.1i release of the software.