Will the Windows XP Mode compatibility tool Microsoft plans to provide for Windows 7 prove a boon to those worried about application compatibility, or is it just a half-hearted kludge to try and convince XP die-hards to upgrade, as some observers believe?

For those not up to speed, Windows XP Mode will be a tool that users can download for Windows 7 that basically provides a pre-configured instance of XP inside a virtual machine. Any software not compatible with Windows 7 can instead be run in this.

A lot will depend upon how XP Mode is implemented, but getting a straight answer from Microsoft is not always an easy matter, as it turns out in this case.

When I met with the company, one question I wanted to know is where document files ended up if you hit the save button in an application running in XP Mode. Would it just go onto the hard drive inside the virtual machine, or has Microsoft been clever and allowed XP Mode applications to map to folders on the host machine?

This is something that Parallels has already implemented in its Desktop for Mac product, which lets Mac users run Windows applications. It means that users don't have to worry about moving documents into the virtual machine in order to edit them with Windows applications.

Has Microsoft done the same with XP Mode? Here is the response I finally got from the company;

"Windows XP Mode is the combination of two features. The first part is a pre-packaged virtual Windows XP environment. The second is Windows Virtual PC, which is used to run the virtual Windows XP environment. Customers can install their applications into Windows XP Mode using typical installation processes such as downloading from the Web or using the product CD. Once installed, the applications are automatically available on the Windows 7 Start Menu and can be launched just like any Windows 7 program. Optionally, these Windows XP applications can be pinned to the Windows 7 Task Bar and launched using just a single click from the Windows 7 desktop."

Like a response during Prime Minister's Question Time in Parliament, this carefully avoids addressing the issue in hand. However, other sources on the web seem to suggest that Microsoft hasn't gone this far, meaning that XP Mode is likely to have a separate file system from the host system. If so, this would be a shame and renders it much less useful than it otherwise would be as a compatibility tool.

I hope to soon have the answer - either by clarification from Microsoft, or by testing the beta of Windows XP Mode and finding out for myself.

30 Apr 2009