European commission expected to fine Microsoft hundreds of millions of euros after software company broke antitrust promiseEuropean Union antitrust regulators are set to hit Microsoft with a hefty fine on Wednesday for breaking a promise to offer consumers using its Windows system a choice of rival internet browsers, people familiar with the case said.The EU competition commissioner, Joaquín Almunia, is expected to use the fine – which could run into hundreds of millions of euros – to set an example after the US software giant became the first company to break a promise made to end an antitrust probe.Almunia will announce his decision at 11.30am, sources said.