The Windows XP Mode that Microsoft is planning for Windows 7 does allow you to access applications straight from the Start menu as promised, and it also enables you to save files straight to the hard drive of the Windows 7 host, I can confirm.

However, in my tests at least, performance was not entirely impressive, with a distinct lag between keys being pressed and the application inside the virtual machine responding.

Windows XP Mode, for those that don't know, is a tool designed to help users moving to Windows 7 if they have any compatibility issues with applications they are currently running.

Still currently in beta, it sets up a virtual Windows XP environment using Microsoft's Virtual PC software.

Users can then install applications inside the virtual machine, which will be available from the  Start menu of Windows 7 afterwards.

The first hurdle a prospective user faces is hardware requirements. Not only does Windows XP Mode require at least 1.25GB of memory (2GB preferred), but it will only run on systems with hardware acceleration for virtualisation. This means you must have an Intel processor with VT-x extensions or AMD processor with AMD-V technology. These must also be enabled in the system's Bios firmware.

I tested Windows XP Mode on a Lenovo ThinkPad X300, which was already being used as a testbed for the Windows 7 Beta. This has a Core 2 Duo L7100 processor that supports Intel's VT-x, but I had to enable this in the Bios.

After installing the new Windows 7 Release Candidate, I downloaded and installed the Windows XP Mode installer, which turned out to be about 445MB in size. Users can also now download it here.

After installation, a new Virtual PC folder appeared in the Start menu, but clicking on the 'Virtual Windows XP' option revealed that Virtual PC itself had yet to be installed. Fortunately, this was automatically downloaded, and a short while later I was fixed up with a pre-configured XP environment.

At this stage, the virtual machine has no applications other than those that come with Windows XP. To install applications, you need to fire up the virtual machine in its normal mode, where the XP screen appears as a window on the Windows 7 desktop (see screenshot).

As you can see, the XP machine automatically maps to the drives available on the Windows 7 machine, allowing you to install software by DVD or hard disk, or by downloading from the Internet.

For test purposes, I downloaded and installed the latest version of the OpenOffice.org suite in my virtual machine, then closed it down. As you can see from the screenshot alongside, the applications now appear in a sub menu on the Windows 7 Start menu.

Clicking an application name starts the virtual machine in the background, but all you will see is the application itself, as if it was running natively on Windows 7. The giveaway is that the application window retains the look and feel of XP, as you can see in the final screenshot below.

The good part about Windows XP Mode is that you can create a document, as I did in OpenOffice Writer, and save it to the My Documents folder on the Windows 7 machine along with all my other files.

The downside is the virtual machine's performance. I found that as I typed text into Writer, nothing would happen for several seconds, whereupon all the characters I had typed suddenly splurged across the screen in one go. This is quite off-putting, and I would hope that Microsoft will address this before the final release is made available.

If you have an application that just won't run under Windows 7, then this solution will get you by, although I personally have found very few applications that don't work with the new platform. However, it remains to be seen whether end users will be satisfied with this. Waiting for an updated version of your application is still likely to be the best option.

06 May 2009