Windows Virtual PC and Undo Disks

With Windows Virtual PC we have been “fine tuning” the user experience for undo disks.

If you are not familiar with “undo disks” this is the feature of Virtual PC that allows you to use a virtual machine, and when you are finished decide whether to keep or discard the changes that you have just made.  This is a very cool and powerful feature – but we have received user feedback that it can be confusing at times.

Specifically, with Virtual PC 2007, trying to close a virtual machine with undo disks enabled will display this dialog:


Which has a total of 7 possible combinations that you can select.  That is a lot of choices to make for just wanting to turn off a virtual machine.

With Windows Virtual PC we have removed the option to “commit changes” from the close dialog.  So now you can only choose to discard changes, or keep them:


Committing the changes in an undo disk is now done as a separate operation through the virtual machine settings on the undo disks settings page:


Here you can view the size of your undo disks, and you can choose to apply or discard the changes from the undo disks.  Note that you can only do this when the virtual machine is not running.