Microsoft has decided to remove a key feature of its next major Windows operating system, codenamed Longhorn, in order to keep its 2006 shipping deadline intact.

Longhorn was expected to come with a major new file system, called WinFS, which is intended to significantly improve the way users can organise and find information on their PCs - this has now been dropped.

The reason behind the decision lies in Microsoft's most recent update, Windows service pack 2 (SP2), which delivered a major revamp to the security features in Windows XP.

Delivering the changes to SP2 meant that many of the company's lead programmers were diverted away from the Longhorn project to focus on the firm's need to improve its security record.

The decision is a reflection of the change in focus at the software company, moving away from delivering more new features in its products and instead ensuring that new products don't arrive with embarrassing security holes.

When it ships in 2006, Longhorn will deliver a range of new features for both corporate and home users, such as a new 3D user interface and the ability to deploy the software more easily across a network.