In spite of the current economic situation, many organizations are upgrading from Windows XP to Windows 7. This really isn't too much of a surprise considering Windows XP turns 10 years old next year. And since few IT professionals dared to touch Vista, running Windows 7 is a logical choice.
But deciding to upgrade to Windows 7 is the easy part; actually migrating, though, is a different matter. Windows 7 is very different from Windows XP, and as a result, Microsoft does not support in-place upgrades. While you can upgrade from Windows XP to Vista, and then from Vista to Windows 7, this practice is frowned upon (and isn't officially supported) because it leaves remnants of two legacy operating systems (OSes) in its wake.
The only fully supported way to move from Windows XP to Windows 7 is to perform a clean installation. While creating and deploying a Windows 7 disk image isn't too difficult, a lot of planning must be done before any large-scale migration.
Which edition should you use?
Deciding which edition of Windows 7 to deploy is the first step in planning your migration. Three different editions of Windows 7 are suitable for businesses: Professional, Enterprise and Ultimate. Windows 7 Professional is mainly marketed toward smaller firms, although it can join a Windows Server domain. Enterprise Edition offers everything the Professional Edition does, in addition to support for Multilingual User Interface (MUI) packages, BitLocker Drive Encryption and Unix application support. Ultimate Edition is identical to Enterprise Edition except for how it is licensed: Enterprise Edition is only sold through volume licensing, whereas individual licenses can be purchased for Windows 7 Ultimate.
Architecture
An advantage of a clean Windows 7 installation is that it doesn't require the same architecture previously used. In other words, you can deploy the 64-bit version of Windows 7 even if you previously ran a 32-bit version of Windows XP.
However, remember that Windows XP is almost a decade old, and as a result, some computers on your network probably don't have 64-bit processors. Therefore, performing a hardware inventory is essential before making 64-bit the new standard.
Application compatibility
When Microsoft released Vista, the company ruffled many feathers as several applications that ran without problems on Windows XP wouldn't work on Vista because of the new User Account Control (UAC) feature. Although Microsoft has toned down that feature in Windows 7, it's still there, and as such, application compatibility testing is a must.
Although UAC receives most of the blame for application compatibility problems, differences in OS architecture can also be at fault. Microsoft has tried to ensure 32-bit applications run smoothly on 64-bit versions of Windows 7, but I have found a handful that simply refuse to run in 64-bit environments.
Similarly, Windows XP supported the use of 16-bit applications. While 16-bit apps are no longer developed, plenty of organizations have legacy applications designed to run on DOS or Windows NT. Windows 7 will not natively run 16-bit applications.
To help with application compatibility, organizations with any of the three Windows 7 editions can download Windows XP Mode. While on the surface, Windows XP Mode looks like a copy of Windows XP running in a virtual machine, there is a bit more to it. Applications installed on the Windows XP VM can seamlessly run through the Windows 7 graphical user interface.
In addition, Windows XP Mode does support 16-bit applications -- but they may not run exactly as expected. For example, a 16-bit installer starts, but it sometimes fails to actually install the application. Microsoft has said that apps that make extensive use of hardware interfaces, like 32-graphics and audio, do not work well in Windows XP Mode. In addition, not all desktops support Windows XP Mode because of the hardware virtualization requirement (AMD-V or Intel VT).
Although Windows 7 offers better backward compatibility than Windows Vista, there are applications that do not run properly on Windows 7. Therefore, hardware and application compatibility testing is essential prior to a large-scale migration.
