Microsoft does not want to support Blu-ray playback natively on Windows 7. It only supports recording to blank Blu-ray disc media.

"Blu-ray (playback) support will be provided by PC makers or BD drive makers. We have new extensibility in media center for those that provide BD playback to support integrated playback. We do have support for burning BD data discs," said Steven Sinofsky, senior vice president of windows & windows live engineering group at Microsoft, in a statement published by the Windows 7 Center website.

The royalties that the Blu-ray disc association demands from player manufacturers holds Microsoft back, not because of the format-war in the past, as the burn option shows. Microsoft promoted HD DVD in the past , together with Toshiba.