Windows 8 was supposed to change how users interact with PCs and how applications are launched, used and integrated. The new operating system and its touch interface were supposed to move users to the latest and greatest ways to interact with apps and data across devices. Incompatibilities have reared their ugly heads, however, causing those who rely on legacy apps to turn away from Microsoft's latest OS before they can reap any benefits.
Interestingly, Microsoft faced similar demons when it rolled out Windows 7. But the company developed technologies to make sure that applications for Windows XP (and earlier OSes) hummed along free of problems. It failed to take the same approach with Windows 8 XP Mode.
The Windows XP Mode add-on significantly eased Windows 7 app compatibility problems. Simply put, a virtual machine running Windows XP became part of the physical PC running Windows 7. XP Mode had some processor and memory overhead requirements, but it was fully integrated into Windows 7.
By design, there is no Windows 8 XP Mode, forcing organizations with Windows 8 compatibility concerns to try various tricks to make their legacy applications work. Some applications still refuse to work properly. Microsoft's lack of support for Windows 8 backward compatibility may be an attempt to finally close the door on Windows XP and force users to upgrade to newer apps.
However, Microsoft's retiring of Windows XP creates a serious problem for those who have to run mission-critical legacy applications for which no upgrade path exists. Businesses have come to rely on countless custom-developed apps, including everything from accounting software to specialized controls for lathes, printing presses and computer numerical control machines. It's unrealistic to expect such organizations to discard their custom tools without Windows 8 app compatibility.
Achieving Windows 8 backward compatibility
Luckily, there is a path to Windows 8 compatibility with legacy apps, thanks to the power of virtualization. Arguably the easiest way to achieve virtual XP nirvana comes from running Windows XP Mode within Windows 8. Although many may claim that is impossible, there are a few tricks to get XP Mode up and running again.
The typical upgrade from Windows 7 to Windows 8 does not delete the Windows XP Mode virtual disk found on Windows 7 systems. The original XP Mode installation is actually installed in a virtual hard disk (VHD) file, which is normally stored in the "C:\Program Files\Windows XP Mode" directory.
That file offers a clean installation of Windows XP, without any modifications or changes that have been made, if you have used XP Mode in the past. That said, those changes and modifications are stored in a separate VHD file, so they can still be recovered after XP Mode comes back to life on the Windows 8 system.
Getting XP Mode fired up on Windows 8 can be a little tricky because it requires an application that can actually run the right virtual machine (VM). Since the XP Mode VHD is stored in a "deactivated" state, not just any hypervisor will be able to launch an XP Mode VM in operational condition. However, VMLite.com offers a free virtualization application, VMLite XP Mode, that is capable of running an XP Mode installation on Windows 8.
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Once downloaded, the wizard-driven installation of VMLite XP Mode imports the existing Windows XP Mode installation and launches the new VM. By default, the VMLite XP Mode installation imports the base VHD file, which amounts to a fresh install of Windows 8 XP Mode.
Any settings or previously installed applications will be missing. They are not lost forever; VMLite XP Mode does provide a way to revive those changes. All you need to do is tell VMLite XP Mode where to find that updated VHD. That is accomplished by changing some settings, importing the proper VHD file and adding it to the media library. The process is driven by a wizard, and goes to "C:\Users\[your username]\AppData\Local\Microsoft\Windows Virtual PC\Virtual Machines\" to find existing VHD files.
When launching a virtual PC, you may be asked to manually sign in. If so, the default username should be "XPMuser," and the password would be the same as used under Windows 7. The first time around, you may have to perform some minor housekeeping chores, such as manually installing the VMLite Guest Additions. You would accomplish this by going to the Devices menu at the top of the XP Mode window and selecting "Install Guest Additions."
With VMLite XP Mode, Windows 8 no longer has to be the end of Windows XP applications. With just a little work, XP Mode can be revived, and legacy applications can once again join the world of the living.
This was first published in July 2013