How To Use Windows Virtual PC to Save Your Old Boot Drive
When you finally make the decision to start fresh with a new OS on a new hard drive, it can be nerve-wracking. If you’ve been following proper hard disk etiquette, most of your programs and data should be stored on different drives or partitions than your operating system, but somehow important data has a way of making its way onto your C: drive. And although you can do your best to make sure you back up all the data you want to keep (your My Documents folder, for instance), it’s hard not to feel like you’re forgetting something.
You don’t have to worry. Thanks to new tools from Microsoft in Windows 7, you can preserve your entire hard disk on another drive as a Virtual Hard Disk (VHD). So don’t worry that you’ll forget important data on your old drive—just freeze it solid, like Han Solo in a block of carbonite, and rest easy knowing that if you suddenly recall that you left something important on your drive, you can simply run it as a virtual PC, or mount it to your new system.
There are several programs that will allow us to accomplish our goal, but only a few that are both free and simple to use. For this how-to, we’ll use Windows Virtual PC and Disk2vhd. Both programs are free, but there is a major limitation: Windows Virtual PC only works with disk images of no more than 127GB in size. Fortunately, this is enough for many Windows XP–era boot disks, but not all. If your drive is bigger than 127GB, you can still create the VHD using Disk2vhd, and you will be able to mount the VHD as an additional hard drive, but you won’t be able to “boot it up” using Virtual PC.
1. Create a VHD
The first thing you must do is create a virtual copy of your C: disk while it’s still your boot drive. This is made very simple with the aforementioned Disk2vhd, which exists for just that purpose. Even better, Disk2vhd works while the disk is online, meaning you can install and run it while still using the drive you intend to clone. Simply download the program here and unzip. When you run the executable, you’ll be asked to specify one or more drives to clone, and an output destination for the .vhd file (image A). Make sure you’ve got another disk with enough space to save the virtual disk, which will be the same size as the original.
That’s all the direction Disk2vhd needs. After that, it’ll take its time making a perfect copy of every disk that you selected in the first step.
2. Recover Data from the Disk
So, now you’ve created your virtual hard disk, installed your new OS, and a month or so has passed. Suddenly, you remember a very important file that you forgot to get off of your old disk. How do you retrieve it from the VHD file? There are two options:
1) Recreate your old machine using Virtual PC
This is the most straightforward case, but it only works as long as your VHD is 127GB or smaller. If it is, you can load it into a virtual machine created by Virtual PC. To use Virtual PC, you’ll first have to download it from Microsoft. At the bottom of the page there are three download options, with the instructions to download them all (image B). You can actually skip the first and third downloads, which simply create a premade virtual machine that will allow you to use XP Mode in Windows 7. (If you don’t have Windows 7 Professional or higher, you’ll have to use Virtual PC 2007.)
To create your virtual machine, simply press the Start button and type vpcwizard into the Run bar. This will walk you through the simple steps involved in creating a new virtual machine for your saved hard drive. The most important step is the one labeled “Add a virtual hard disk” (image C). Here, click the second radial button, labeled “Use an existing virtual hard disk” and browse for the disk you created earlier. When you’re done with the wizard, you’ll have a virtual version of your old machine, which you can use to locate any old files or applications you may have forgotten.
2) Mount the virtual drive
If your VHD is too large for Virtual PC, you can still mount it to your new computer as a regular hard drive. To do this, first open the Computer Management window by clicking the Start button, then right-clicking Computer and selecting Manage. In the Computer Management window, click Disk Management, then click Action and select Attach VHD (image D).
You won’t be able to boot from the virtual disk, but you should see it in the Windows explorer as though it were a real hard drive. You can now browse through its contents and find any files you need.
Comments
Comments are closed on this article
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Michael Ellis
November 16, 2010 at 2:18pm
It is trying to get me to reactivate windows and then tells me that my license is invalid. Is there anything I can do?
Never Mind. I figured out that the new version of disk2vhd has a special setup and that you just enter the product key on the error page for the activation.
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RobertDennis
August 28, 2010 at 7:36am
Virtual PC does work with Windows 7 Pro, there is even a VHD for XPMode which is a 32 bit XP virtual machine.
Also with a large VHD as long as the content doesn't exceed 127GB you can attach to the system, shrink the volume to under 127GB
You can then use VhdResizer to resize the disk to use in a virtual machine.
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w7pro
August 15, 2010 at 5:35pm
Alex, thanks for this valuable information on how Windows 7 Professional helps preserve your entire hard disk on another drive as a Virtual Hard Disk. Andrea H. Windows 7 Professional Outreach Team @Win7ProSB
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Mike0
August 05, 2010 at 8:50am
I recently purchased a new pc and have been trying to get this to work without any success; any help would be appreciated.
Reading other forum sites, I think the problem is that I created a virtual disk from my old PC which was running Windows 7 Ulitmate 64 bit. According to other forums, virtual pc can't load a VHD created with a 64 bit OS. Can anyone confirm this?
Details:
old pc: Windows 7 Ultimate 64 bit
new pc: Windows 7 Ultimate 64 bit
I created a VHD from the boot drive of my old pc. The boot drive is 150GB (only about 80GB being used). VHD was greater than 127GB so I resized it with 'vhd resizer' program so it was 110GB. (I also tried to change the partition size of my old boot drive but the VHD was still bigger than 127GB).
On the new pc, I can load the VHD in virtual pc but it goes into an endless loop where I see a 'dos' screen where RAM is checked, then a message (something like) 'windows is loading files', then it goes back to the RAM check, 'windows loading files', etc.
I can access the BIOS setup screen in virtual pc but I can't boot to windows safe mode.
I can attach the VHD as a virtual drive and access all of the files but I'd really like to load it in virtual pc to be able to run my programs until I get around to reinstalling my apps on my new pc.
Please help
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tonyaldr
August 04, 2010 at 2:23pm
It would be great if you can use the VHD as an image (similar to Ghost) to recreate your boot disk on a new, perhaps larger hard drive. Any way to do this?
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dwr50
August 04, 2010 at 6:27am
It's easier to use Virtualbox to make the VHD and there is no size limit.
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sammy_sam
August 03, 2010 at 5:56pm
Buy a new hard drive....then just slap the old hard drive in your computer after reinstalling the OS and browse to whatever files you need or just drag everything over from the old drive to the new one.??? Then you don't have to go through the above hassle of having a "virtual" hard drive when you've already got the real deal?
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The Relic
August 03, 2010 at 6:32pm
Well, since the whole point is to do this on the cheap, why buy a new HDD when you can just make a VHD and still have access to your data? Then, when you are sure you have all your data off it, delete it or keep it to test programs on. Either way you have no added expense.
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tri8gman
August 04, 2010 at 12:08pm
"When you finally make the decision to start fresh with a new OS on a new hard drive, it can be nerve-wracking"
The article starts out with "new OS on a new hard drive" - what part of this did you miss?
Without a second drive, I don't see how you'd do this to begin with. If you wanted to be cheap and use the same hard drive and weren't changing file systems, you could use a Live CD or other boot tool to move everything into a folder - OS and all, depending on your drive size needs. If your drive is too full for that or you're changing file systems, then you definitely need a second drive, making it all moot.
This VHD shit seems more for "I forget how I installed this program" or "I don't have my installation files for this program anymore" or "The new OS won't work with my old program!"
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Pokedex1010
August 03, 2010 at 4:34pm
I'm in the middle of it right now, what are the chances. Great "How to" and keep up the good work
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