The European Court has rejected Microsoft’s appeal against an EU ruling finding the software company guilty of abuse of its market dominance.

A €497m (£345m) fine and an order to share details to allow interoperability for competitors' products have been upheld.

The Commission also ruled that the bundling of Windows Media Player with Microsoft’s Windows PC operating system affected competition.

The decision to order Microsoft to offer for sale a version of Windows without Windows Media Player has also been upheld.

Under the ruling Microsoft is required to disclose specifications of its client/server and server/server communication protocols to competitors wishing to develop and distribute workgroup server operating systems.

On 7 June 2004 Microsoft had brought the action before the Court of First Instance for annulment