Microsoft has announced that Halo 2 from Bungie will only be playable on its Windows Vista operating system.

The move is likely to enrage gamers looking forward to playing the Master Commander on the PC.

While the original PC game, ported from the Xbox in 2003 was available for all versions of Windows, the software giant has said that the latest version will be Windows Vista only.

In a informal posting from the content manager on Bungie's website, the company says: “It will also add layers of new functionality, speed, media processing and so on. I have heard a rumor, in fact, that it will replicate a lot of the functionality of them new-fangled Media Center PCs so that you can stream HD and whatnot to your Xbox 360. If that's true, that would also be nice.”

He went on to say - “there will be significant differences between the PC and the Xbox version. The PC for example, invariably runs at resolutions that aren't 480i.”

One HUGE difference between Xbox and PC versions is the absence of Xbox Live. But don't worry, we'll have a cool system for that, no doubt.”

“There will also be some kind of map-customization ability. Does that mean you can build your own maps from scratch, pixel by pixel, importing your own textures, scripts and detailed shaders? Or does it mean one empty room and a crate? Well, we'll have more news on that later this year, but it will be cool, we guarantee that.”

The story eludes to much more to come so we will keep you posted.