The head of Microsoft's Japanese unit has said EC (European Commission) fines levied against Microsoft will not affect the launch of the Windows Vista OS (operating system).

Yesterday, the EC fined Microsoft €280.5m (about £194m) for failing to comply with the terms of a March 2004 antitrust judgment against it. As part of the judgment, the software giant was ordered to provide competitors with technical details of communications protocols used by its server products. The fine was imposed to punish Microsoft for failing to do so quickly.

"What the EU [European Union] wanted was not that specific until April. We agreed to a set of milestones and we're hitting those milestones, but the last milestone is a week or so away," said Darren Huston, president and CEO of Microsoft's Japanese unit.

The fine will not affect the launch schedule for Windows Vista, Huston said at a news conference today. The company's new OS is scheduled to be available through volume licensing in November and through retail to consumers in early 2007.

The OS is already in beta testing. At this stage the biggest threat to the schedule would come from a beta tester finding a serious problem in the software that would require significant amounts of work, Huston said. However, as the release date approaches, the probability of finding such a flaw decreases, because it would probably have been caught already.