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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A consumer report found that a number of once-a-day sunscreens decreased in protection by an average of 74% after six to eight hours.
It will be mainly dry across the UK, but parts of Wales and England may experience thundery showers.
New report from the Public Accounts Committee says courts are beset by 'long-standing poor performance', causing delays for victims.