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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The business group is warning Theresa May she is running out of time to make progress on a Brexit deal.
The attacks came as Erdogan promised to expand Turkey's border operations against a US-backed Kurdish group in the fight against IS.
The Office for Product Safety and Standards will manage responses to large scale product recalls and identify risks to consumers.