The Windows 7 service pack 1, rolled out between mid-2011 and mid-2012, failed to offer consumers a choice of browser, leading to the EU investigation that resulted in today's fine.
Microsoft said the failure was the result of a technical error and that procedures have since been tightened.
In what was seen as an acknowledgement of the severity of the mistake, the board cut the bonus of chief executive Steve Ballmer last year, according to company's annual reports.
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Peers have rejected to vote through the Government's Brexit Bill in the first major setback for the legislation.
Teresa Dennett needed emergency surgery but she died after a row over hospital catchment areas and because of a lack of critical care beds.
The move will put 400 jobs at risk.