EU opens Microsoft antitrust probe over web browser

"We are now opening formal proceedings," European Union Competition Commissioner Joaquin Almunia told a news conference. "If infringements are confirmed, there will be sanctions."

In order to avoid EU sanctions in 2009, the US software giant had agreed to provide Windows users in Europe a "choice screen" enabling them to choose a web browser instead of Microsoft's default Internet Explorer.

But the choice screen appears to have disappeared when Microsoft rolled out Windows 7 Service Pack 1 in February 2011, depriving about 28 million people of the option of choosing their preferred web browser, Almunia said.

"Microsoft has recently acknowledged that the choice screen was not displayed during that period," the commission, the EU's antitrust regulator, said in a statement.