This week, Microsoft has updated the set of offerings which permit end users to access free copies of Windows Vista and Windows XP SP2. Despite the fact that giving out free versions of its operating system contradicts the Redmond company's proprietary business model, both its latest Windows client and its predecessor are up for grabs at no charge at all. The downloads are made available via the Internet Explorer Application Compatibility VPC Image.

The first Internet Explorer Application Compatibility VPC images were delivered at the end of 2006, after the offering of Internet Explorer 7. Microsoft wanted to satisfy the need of web developers to build, run and test their content on both IE7 and IE6, while using the same operating system. Virtualization provided then the right answer for the Redmond company.

The IE Application Compatibility VPC Image were updated last concomitantly with the release of Internet Explorer 8 Beta 1. In early March 2008, Microsoft delivered three free pre-activated copies of Windows XP SP2 designed to run IE6, IE7 and IE8 Beta 1, as well as one copy of Windows Vista with IE7.

The downloads offer Virtual Hard Disk Images of both XP SP2 and Vista RTM, which have to be integrated with Virtual PC 2007. Each download provides a separate VHD which can be used to create virtual machines with Vista and XP SP2.

"VPC Hard Disk Image for testing websites on IE on Windows XP SP2. A VPC hard disk image containing a pre-activated Windows XP SP2 or Windows Vista, and IE6, IE7 or IE8. This VPC image will expire on July 3, 2008. You will need a minimum of 1.5 Gig hard drive space free to expand the VHD file. Once you have completed the download, double-click file to expand the VHD file. Start Virtual PC and create a new VPC, and point to the files you just expanded," Microsoft revealed.

Internet Explorer Application Compatibility VPC Image 3.0 is available for download here.