REDMOND, Wash. — Microsoft Corp. said Thursday it will share more information about its products and technology in an effort to make it work better with rivals' software and meet the demands of antitrust regulators in Europe.

European Union regulators, however, expressed skepticism, saying the software maker did not address monopoly abuse in the past or allegations it seeks to undercut rivals by bundling Internet Explorer with the Windows operating system.

Microsoft said it is expanding access outside software developers have to information about the way its programs work. The software maker said it will give away documentation and computer code needed to make outside applications work together with Office, Windows and others. In the past, Microsoft charged for this information. The company will still charge a fee to companies that sell software built using this information, which one officer called "low royalty rates."

CEO Steve Ballmer said the decision will have a minimal impact on revenue.