However, the company would not confirm specific reports that Hewlett-Packard Co. has been given the green light to sell new PCs with Windows XP Professional preinstalled through the end of April 2010.

"Based on feedback, Microsoft is further broadening the options provided to Direct OEMs to help customers facilitate End User downgrade rights included in the product license terms of a new system with either Windows Vista Business or Windows Vista Ultimate," said a Microsoft spokeswoman in an e-mail. "This option is designed to help Direct OEMs further support customers, primarily small business customers, looking for Windows XP Professional due to application compatibility concerns."

On Saturday, that Microsoft had given HP the okay to offer Windows XP as a downgrade through April 30, 2010.

that allows users -- and in their stead, computer makers -- to install Windows XP Professional while also providing media for Vista for a possible upgrade later. In effect, the license for the newer Windows -- Vista -- is transferred to the older edition, XP.

Microsoft allows owners of only Vista Business and Vista Ultimate -- the two highest-priced editions -- to downgrade to XP.