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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Dozens of people have been evacuated from a Russian ship after a collision in the Black Sea.
It comes just days after a father streamed himself murdering his daughter before killing himself on the social media platform.
Still got an old style paper £5 note? Well, you only have until Friday to spend it in shops before it ceases to become legal tender.