In a Monday announcement, Microsoft said that it has extended the downgrade period for Windows XP till 2020; thereby giving the owners of some Windows 7 versions the choice to “downgrade” to the operating system for up to a decade. The downgrade rights allow customers to substitute a newer version of Windows with an older edition without needing to pay for two copies.

The move of extending the downgrade is a highly surprising one because Microsoft had earlier terminated the downgrade rights within a few months of unveiling the new OS version.

When the Windows 7 version was released, Microsoft had limited the 7-to-XP downgrades to six months; however, it soon extended the rights almost immediately. The company changed the date till July 2010; and, with that having gone now, Microsoft has further increased the extension.

However, the downgrade rights are available only to the users of Windows 7 Professional or Ultimate, who can downgrade to XP Pro. Moreover, with the rights available only on OEM copies of Windows 7; the version should come pre-installed on the new PC of the users.

Elaborating further, Microsoft spokesman Brandon LeBlanc said in an entry on the company blog: “Going forward, businesses can continue to purchase new PCs and utilize end-user downgrade rights to Windows XP or Windows Vista until they are ready to use Windows 7.”