Issue using Heidi Eraser on vmware fusion

I have had a rather unpleasant issue. I have (had actually) windows 8.1 installed on vmware fusion 5.0.5 . The image was not preallocated. The idea was that by running Heidi Eraser and zeroing unused space, the image would be more compressable.

I decided to run the eraser on the entite disk. The computer just dropped dead. Worse yet. The operating system would not boot. So I have to reinstall. Not funny. Of course, I should have made a snapshot.

I have no idea why this happened.