European Union authorities have raised fresh anti-trust concerns about Microsoft's business practices.
The company acknowledged on Friday that it had received a Statement of Objections from the European Commission regarding its bundling of Internet Explorer with new copies of Windows.
Internet Explorer is currently shipped with the operating system, and set as the default web browser. Microsoft retained the right to bundle the software when it agreed to a settlement with US authorities as part of its landmark 2002 anti-trust ruling.
However, no such deal was reached in Europe, and the Commission still believes that the practice violates EU competition laws. Microsoft said that it plans to respond to the concerns within the next two months.
"We are committed to conducting our business in full compliance with European law. We are studying the Statement of Objections now," the company said in a statement.
The filing is the latest in the ongoing anti-trust battle between Microsoft and the European Commission. The two sides have been in talks since 1998 over the company's business practices, and its willingness to co-operate with other software vendors.
The most recent clash came last year when the EU fined Microsoft €899m (£814m) for its failure to give other vendors adequate information on how to develop interoperable software for Windows.
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