Upgrading your computer to a new operating system is rarely pleasant and frequently very difficult. Although some operating systems make a decent fist of in-place upgrades, where you run an installer program and your old data and applications are automatically transferred across, Windows is not good here. Even if you do get all your stuff onto the new computer, there's always the danger that some will be incompatible with the new system - and at the very least, there are many new things to learn before you can become as productive as you were when using the old, familiar setup.
Which is where virtualisation is tremendously helpful, as it lets you create a software copy of your old system that runs on the new. You can move stuff across at your leisure and move back to the familiar environment almost instantly. It's one of the great advantages of virtualisation: old software doesn't have to die no matter how you upgrade.
It's such a good idea that Parallels, the company best known for its Mac virtualisation product, created a $50 utility - Parallels Desktop Upgrade to Windows 7 - to do just that. However, as American CNet colleague Ina Fried has discovered, this is causing something of a ruction with Microsoft - for, although there is no technical or practical problem with this, Microsoft's standard licence means you can't run Windows XP as a virtual machine. Not allowed.
"Microsoft does not endorse moving the user's desktop from a physically loaded OS into a VM as a consumer solution, because the vast majority (more than 90 percent) of consumers do not license Windows under a license that would allow them to transfer Windows into a virtual machine, move Windows to a different machine, or run a secondary virtual machine that is not running XP Mode on the same machine," Microsoft's general manager, Gavriella Schuster, said in a statement to CNET. "Without these license rights, most consumers will not be properly licensing Windows when using the virtualization features of Parallels' product."
Parallels says that it's the user's responsibility to make sure they have the right licence, which of course it is, and that there's absolutely nothing wrong or illegal about the utility, which of course there isn't. And users could care less: a straw poll in the ZDNet UK office revealed that 100 percent of users would ignore Microsoft's licensing restriction - "If you retire the old machine, there's nothing wrong with virtualising it. It's not natural justice," said one.
It would certainly be interesting were Microsoft to prosecute anyone for doing this, as it would be a most useful test of the EULA condition that forbids it. Licence restrictions have to fall within consumer law to be binding, and unreasonable ones do not. Is this one unreasonable? Everyone here thinks so.
For now, though, Microsoft seems content with putting pressure on Parallels to effectively slap "DO NOT USE THIS SOFTWARE: 90 PERCENT OF YOU ARE EVIL IF YOU DO" over its product - or similar. "Microsoft is working with Parallels to ensure that the Windows licensing requirements are made clear to customers in their product," Schuster told CNet.
Exactly why would Microsoft be concerned that people are doing something so seemingly benign as carrying on using an old operating system they'd paid for at the same time as a new one they'd also paid for?
I was told some time back, by a well-informed observer, that the company sees virtualisation as a direct danger to one of its most important revenue streams - the one that means you have to buy a new operating system when your hardware becomes obsolete or dies. Otherwise, that copy of XP could live for ever, skipping into the future from machine to machine, and Microsoft wouldn't be able to charge you every three years or so for a new OS whether you needed it or not. And as a virtualised XP runs just as happily under Mac OS or Linux as it does under Windows 7, it clearly can't be allowed.
I don't actually know this to be the case, but it's the only explanation - not just the best one, it really is the only one - that fits the facts. If I am wrong, I will be delighted to be put right by Microsoft, just as soon as it tells me what's really going on - and will pass it on with alacrity.