Windows Virtual Machines will not run
This solved it for me: http://timwise.blogspot.com/2012/04/running-ie-application-compatibility.html
For me the image would get half way through booting windows, and then blue-screen (BSOD). I discovered that it was possible to get past this by removing the SATA controller the machine's settings, and instead adding the disk under the IDE controller. After that the machine booted successfully.
Basically you have to remove the SATA image and re-add as IDE.