When Microsoft released Windows Vista, it received a lot of backlash since many of the applications that had been designed for Windows XP wouldn't run on the new OS. In order to appease Windows XP's rabid fan base, Windows 7 was designed to include something called Windows XP Mode.
In a nutshell, Windows XP Mode is a Windows 7 add-on that runs a full-blown copy of Windows XP from within a virtual machine (VM). Users can work with the familiar Windows XP interface, or they can access their legacy applications through the Windows 7 interface, even though those apps are actually running on a VM.
It's obvious Microsoft created Windows XP Mode as a marketing tool to convince organizations still running XP to upgrade to Windows 7. But is it better to use XP Mode and stick to an existing Windows XP deployment or abandon legacy applications and use Windows 7 without XP Mode.
Although XP Mode is an innovative solution to the compatibility problems posed by some legacy applications, I think it should be used only as a last resort.
Don't get me wrong -- there is nothing wrong with XP Mode. It works really well. Even so, deploying it onto Windows 7 desktops adds a layer of abstraction to the desktop. This extra layer can complicate technical support, affect the desktop's performance and increase the size of the desktop's attack surface.
Luckily, it's often possible to run legacy applications on Windows 7 without resorting to XP Mode. Many of the compatibility problems that plagued Vista have been corrected in Windows 7. Therefore, if you are considering upgrading to Windows 7, you should take an application inventory and test all your apps in a Windows 7 environment. Also note that Microsoft provides a plethora of application-compatibility information through the Application Compatibility Toolkit .
If you determine that your applications are compatible with Windows 7, then there is no need to deploy XP Mode. The apps can be installed on Windows 7 in the same way that you would install them in Windows XP.
Legacy applications sometimes have minor compatibility problems that can be resolved by using the Windows 7 Program Compatibility Assistant. This method – if possible -- is preferable because the Program Compatibility Assistant does not incur the performance hit that XP Mode does.
But what happens if your legacy apps are not directly compatible with Windows 7 and can't be tweaked through the Program Compatibility Assistant? Well, in these types of situations, you should consider if the application is necessary. Almost every organization has at least a few apps that nobody uses. If your incompatible application falls into this category, you could save yourself a lot of trouble by retiring it.
If the incompatible application is something the company still uses, then you might check to see if a newer version is available. A newer version could solve compatibility problems and let you avoid having to resort to XP Mode. Of course, a newer version of the software may not exist, or the cost of licenses for the new version may exceed your budget. At that point, you really have no choice but to use Windows XP Mode or continue using Windows XP.
So what should you do? The primary advantage to continuing to use what you already have is cost. The OSes are already paid for, as is the desktop hardware. To upgrade to Windows 7, you have to purchase new OS licenses, and you may have to replace some older desktop PCs. You may also have to invest some money in Windows 7 training for your users and support staffers.
On the other hand, Windows 7 seems to do a better job of supporting newer hardware. It also seems that Windows 7 is much less prone to malware infections than XP is. Sure, XP Mode involves running a full-blown version of XP within a VM, but users in many organizations work from within the Windows 7 interface. The XP operating system's only job is to run applications that are not compatible with Windows 7. As such, the user is protected from many of the security problems that have plagued Windows XP.
If your organization is still running Windows XP, upgrade to Windows 7 if it's practical for you, but try to avoid using XP Mode unless you have to.
ABOUT THE AUTHOR
Brien M. Posey, MCSE, has received Microsoft's Most Valuable Professional Award seven times for his work with Windows Server, IIS and Exchange Server. He has served as CIO for a nationwide chain of hospitals and health care facilities and was once a network administrator for Fort Knox. You can visit his personal website at www.brienposey.com.
This was first published in November 2010