A Parallels technical article entitled Critical and Urgent Windows 8 Service Advisory warns users of Parallels 8 for Mac that upgrading virtual machines to Windows 8 could result in data loss. The company advises that users should run the latest update of Parallels 8 before upgrading, and to make a backup of the virtual machine before upgrading it to Windows 8. In another technical article about installing Windows 8 in a virtual machine, Parallels warns that upgrading from a DVD can result in the loss of all Windows files, applications, and settings:
If you create installation media to install Windows 8, and then start your Virtual Machine from that media and install Windows 8, you won't be able to keep your previous files, programs, or settings. To keep files, programs, or settings you must install Windows 8 by starting the installation from within your current version of Windows.
The Service Advisory states that creating a new virtual machine with any of the Windows 8 versions "should work just fine." VMware Fusion 5 can also run Windows 8 in a virtual machine on a Mac.
If you're using Windows 8 on a Mac
how it's working.