Last updated at 19:48 17 September 2007

Computer users were promised better and cheaper products yesterday after Microsoft lost a three-year European legal battle.

In a ruling described as a major victory by consumer groups, a Brussels court confirmed that the software giant must make it easier for rival systems to work with its Windows operating system.

It means that Microsoft must disclose its secret computer codes to enable rival companies' gadgets such as media players to work seamlessly with Windows personal computers when downloading songs and videos.

The European Court of First Instance, the EU's second-highest court, also ruled that the world's biggest software company must pay a £343 million fine imposed in 2004 by the watchdog European Commission when it ruled that Microsoft abused its near-monopoly position to freeze out competitors.

Jim Murray of BEUC, a consumer organisation, said:

"The decision should bring more competition in the market and more incentive for other companies - and for Microsoft - to offer improved products and services at a competitive price."