Microsoft have added some fantastic features to Windows in recent years.  Top of my list is Complete PC Backup, a service that really does exactly what it says on the tin, and that can restore a faulty copy of Windows to a fully-working version in as little as ten minutes.

Needless to say when I first heard that Windows 7 would allow booting from virtual hard disks (VHD), copies of windows installed inside files on your hard drive, I had high hopes.  Many of my friends are hard-core gamers and quite attached to the performance of XP.  No matter how fast Windows 7 turns out to be, I knew it would be hard to tear them away from their favourite gaming operating system.

I’ve done some playing around with the boot from VHD option now and I have to say it’s the biggest single disappointment in Windows 7 yet, yes even more than the new taskbar I keep banging on about.

The problem stems from the fact that you can only use it to boot into installations of Windows 7 or Windows Server 2008.  I’ll lightly skip over why anyone would want to install Windows 7 on a machine and then boot into a server OS.  Having this feature in the server OS itself makes sense but not like this.

So what does this mean for business?  These are the people who will most likely want to use this feature after all.

System admins will be able to install Windows 7 on a PC (requiring a licence activation) and then install a protected version of Windows 7 into a VHD inside that (requiring another licence).  Staff will then be able to boot into the protected version of Windows 7 and never cause any damage to the original.  But what if something gets corrupt in the VHD installation?

At this point the administrator will need to boot Windows into the original copy of Windows 7, an option they’ve probably hidden anyway, and copy the VHD file back from a backup.  This is a procedure that’s more fiddly and will take longer than performing a complete PC restore, an operation for which you no longer need an original Windows DVD to perform anyway.

This is on top of the fact that Windows 7 now has a facility called PC Safeguard, which will automatically dump any changes made to a copy of Windows or its installed software when you log off or shut the machine down.  This prevents anybody from damaging the Windows installation or changing any settings.  So why the need to run a second copy of Windows (remember you still have to pay for this second copy) at all?

Then we move onto the biggest and most common reason to want to run any operating system in a virtual machine, application compatibility.

Most companies and people who will want to run a virtual machine will do so because some software won’t run happily unless it’s on an older version of Windows.  But as the boot from VHD system won’t allow you to boot from an earlier version of Windows, you’re back to needing a traditional dual-boot system or foregoing Windows 7 altogether.  This doesn’t seem to make financial sense for Microsoft.

There are no doubt sound technical reasons why the system isn’t able to trick your computer’s BIOS into thinking there’s an extra drive, but surely the system can create a virtual environment that will allow you to get a Windows XP (etc.) CD started.  It won’t even allow you to boot from a VHD created using the latest version of Microsoft Virtual PC.

The cherry on the cake is that the only way to configure the system is from within a DOS command Window.  WHAT!?  Windows 7 includes the new scripting control language powershell for system administrators.  DOS was supposed to have gone the way of the Dodo years ago.

I began this article by saying that I had very high hopes for this facility.  I believed it to be the crown jewel in Windows 7′s cap that complete PC backup was for Vista.  Working properly this feature has enormous potential on the desktop to transform the way that we work with gaming and legacy applications.  I have to say though that I am tremendously disappointed all round.