How to mount a VHD which is on an external USB hard drive

Question

I have Virtual PC 2007 and I have a VHD on my external harddrive. The vhd is from a complete Vista omputer backup. When I follow the wizard it gives me two options both relating to compacting the VHD. Is there anyway I can simply mount it, AS-IS . Not sure if it will matter but, the VHD is 150GB and the temp computer I am currently on only has 23GB of free space which is why I simply want to mount it and use as is.

Answer 1

If you are running Windows 7 this can be done using Disk Management.

• Open Computer Management
• Select Disk Management
• Right Click on Disk Management
• Select Mount a VHD file

However if you are running anything below Windows 7 this is not supported.

Answer 2

If one is using pre-Windows 7 operating systems (e.g., Windows XP or Windows Vista), this can be done using the utility vhdmount, which comes with Virtual Server. Virtual Server is also a free Microsoft product and can be installed to get one's dirty little hands on vhdmount.

One caveat is that one has to run vhdmount from a command-prompt with elevated permissions, otherwise it keeps failing silently. So what you would do is, right-click on the command-prompt icon in the start menu, and then select "Run as Administrator", and then issue the vhdmount commands at that prompt.

Please pay special attention to the command-line parameters of vhdmount, as you can mount a VHD file and have vhdmount discard all changes to that disk image when the disk image is unounted. Of course, if you are saving your PhD dissertation to that mounted VHD image, and all changes are discard, that might be detrimental to your blood pressure :)

Therefore, first run a simple test to familiarize yourself with vhdmount.