Backing up volume shadow copies in Windows 2008 (Hyper-v) Virturals using Diskshadow

The script I had for backing up my Windows 2005 Virtual server does not work in Windows 2008 using Hyper-v. So I started looking for another solution. Here is what I'm doing to backup my Virutal servers in Windows 2008. In Windows 2008 there is a new tool called "diskshadow". This link below shows how to use it and they have a script to get your started.
http://technet2.microsoft.com/windowsserver2008/en/library/e962537d-b759-4368-b6f1-e8391cf7b2211033.mspx?mfr=true
I don't need to create a shadow copy of my system drive nor to mount it, so I just commented out the two lines:
#add volume c: alias SystemVolumeShadow
#expose %SystemVolumeShadow% p:

For testing I run this command from the command prompt: DISKSHADOW /s script.dsh
If all is well I set up a task schedule to run this.

So what this script does is create a shadow copy and mounts it to the P and Q drives. I don't need the mount to P so my script will only mount my shadow copy of my D drive to Q. I then have a script that runs an xcopy command to backup my "virtual servers" folder to my USB hard drive which is mounted to the I: drive.

The last line of my backup script is to remove the Q: drive mount. If you don't remove the mount before you run the script you will get an error. So unmount the shadow copies that are mount before running the script. To unmount use this command. "mountvol driveletter:\ /D"

So the last line in my backup script I have "mountvol P:\ /D" so that the P: drive is available the next time I run the script.dsh the P: drive is available to mount to.