Microsoft will have to pay a record half billion euro fine and share confidential details of its code after a court today upheld European Commission sanctions against the company for abusing its market dominance.

The EU's Court of First Instance has dismissed a plea for Microsoft to be freed from the penalties while the software giant fights them on appeal.

In its ruling, the Court noted dryly that Microsoft could afford it. It said: "The evidence adduced by Microsoft is not sufficient to show that implementation of the remedies imposed by the commission might cause serious and irreparable damage."

The commission imposed the €497 million (£344 million) fine in March after finding that Microsoft had abused its overwhelming dominance in the software market for personal computers.

The company was also ordered to provide competitors with confidential coding information, and to offer a European version of its Windows operating system without its Media Player software, which offers access to audio and video content.

Microsoft had argued that it would suffer "serious and irreparable damage" if forced to make concessions which might yet be overturned on appeal.

However, the court said: "After examining the circumstances of the case, the president finds that Microsoft has not shown that it might suffer serious and irreparable damage as a result of implementation of the contested decision."

Microsoft said that it would take a close look at the court order before deciding on its next steps.

However, it said that the judgment had offered it some gains.

"The court recognised that some of our arguments on the merits of the case are well-founded," Microsoft said, adding that such an appreciation could help the company in its appeal.

However, Philip Carnelly, the Ovum EuroView research director, warned that the ruling could have broad-ranging effects.

"It will come as a surprise to many that the judge's decision was so firm, dismissing Microsoft's appeal completely," he said.

"The consequences for Microsoft, and the industry as a whole, are potentially very wide-ranging."

Doubts had been raised in particular about Microsoft's freedom to roll wide-ranging products together a comprehensive Windows package, a process know as bundling.

Mr Carnelly said: "This judgment may well be seen to have altered the course of the industry. Until this time, bundling was the clear winning strategy."

Dave Stewart, the deputy general counsel for RealNetworks, a Microsoft competitor in the market for software for handling video and audio files, said: "The court has taken an important step toward promoting robust competition... fostering technological innovation and giving consumers real choice."

Times Recommends

• Lies and cover-up at MG Rover exposed by report
• High oil prices push manufacturing costs up
• Primark founder steps down as chief executive