I have looked so long for this; a short and sweet description on how to compact Virtual PC images. Here it is: http://kurtsh.spaces.live.com/blog/cns!DA410C7F7E038D!1902.entry
- Clear out the machine of filler I recommend installing CCLEANER.EXE from http://ccleaner.com which deletes all temporary files from the Windows installation, Internet Explorer cache, the Recycle Bin, and any number of other “garbage”/”temp” directories in the VPC.
- Disable hibernation If you have hiberation turned on, there’s a colossal sized file called hiberfil.sys in the root of the .VHD. Go into Power options in Control Panel and disable hiberation to get rid of this file.
- Capture the Virtual Disk Precompactor .ISO In the menu of Virtual PC windows for your machine, capture the Virtual Disk Precompactor .ISO file which is located at: c:\program files\microsoft virtual pc\virtual machine additions\virtual disk precompactor.iso
- Run the Precompactor Go to My Computer and double click on the mounted disk. It will begin to run the precompactor software which will essentially zero out all the free space on the disk, making it available for elimination from the file by the Virtual Disk Wizard, which we will use later. This process may take upwards of 15 minutes
- Shutdown the Virtual PC
- Run the VPC2007 Virtual Disk Wizard From the Virtual PC console, click File-Virtual Disk Wizard and “Edit an existing virtual disk”. It will ask you to identify the .VHD file to reduce in size - select it.
- Compact the .VHD Select the “Compact” option then select “Replacing the original file”. This will take a few minutes.
One thing to note is that bullet point 3 describes that you should attach the .ISO image that is referenced. This can be done directly in Virtual PC and the menu command is called capture (CD -> capture ISO image…). Maybe self explanatory for some but I looked around a while for that one…