According to an article on Mac Observer, Parallels, makers of the popular Parallels Desktop for the Mac, is alerting its customers that they'll run into End User License Agreements (EULA) when running Windows Vista in a virtualization-based environment such as the one Parallels provides.

According to Vista's agreement, which the user essentially signs when they click the "Agree" button, is that the Home Basic and Home Premium editions of Microsoft's recently released operating system are not licensed for use in a virtualization environment. In order to run Windows Vista in a virtualization format the license agrees with, users will have to look into the $299 Business edition as opposed to the less expensive home versions.

The Vista EULA's provisions regarding virtualization are as follows:

"USE WITH VIRTUALIZATION TECHNOLOGIES. You may use the software installed on the licensed device within a virtual (or otherwise emulated) hardware system on the licensed device. If you do so, you may not play or access content or use applications protected by any Microsoft digital, information or enterprise rights management technology or other Microsoft rights management services or use BitLocker. We advise against playing or accessing content or using applications protected by other digital, information or enterprise rights management technology or other rights management services or using full volume disk drive encryption."

The warning appears to invalidate the user from using DRM-protected content, though final details have yet to emerge.

Citing a story on OSNews, users have apparently pointed out that after upgrading their Windows PCs from Windows XP to Windows Vista, their Windows XP licenses had been voided.

Apple's Boot Camp has been cited as a way to work around the virtualization issue, although this doesn't resolve the issue for users who want to run Windows Vista simultaneously with Mac OS X.

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