The European Commission (EC) has initiated two new formal antitrust investigations against Microsoft for interoperability and tying software together.

Following complaints made by web browser vendor Opera Software and the European Committee of Interoperable Systems (ECIS), concerns have been raised over Microsoft tying its Internet Explorer to its Windows operating system, making it difficult for rivals to compete.

In September last year (CRN, 17 Sept 2007) the ECiS filed a complaint saying Microsoft had allegedly refused to disclose interoperability information across a broad range of products, including the bundling of its Media Player software.

The decision by the EC comes just four months after the Court of First Instance confirmed that principles must be respected by dominant companies in regards to interoperability disclosures.

In a statement a representative for Microsoft said: “Microsoft will cooperate fully with the Commission's investigation and provide any and all information necessary. Microsoft is committed to ensuring that it is in full compliance with European law and our obligations as established by the European Court of First Instance in its September 2007 ruling.”

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