Nearly 20 years later, the decision to bundle a web browser with Windows is still giving Microsoft grief. Today, the European Union has decided to fine the company €561 million (around $732 million) for breaking a 2009 antitrust agreement. At the time, Microsoft agreed to include a browser ballot box in every new copy of Windows, allowing users to pick any one of the 12 most popular browsers rather than defaulting to Microsoft Internet Explorer. However, in what Microsoft called a "technical error", Windows 7 Service Pack 1 removed this choice. In July, the European Commission formally started investigating, and last October it decided that Microsoft had indeed broken the rules.

Last month, Reuters reported that the EU would likely fine Microsoft by the end of March. Indeed, Microsoft is now paying for the trouble. The commission noted that this is the first time a company has ever been fined for "non-compliance with a commitments decision."

Today's €561 million fine is in the same region as the enormous €899 million (roughly $1.44 billion) fine levied by the EU back in 2004, and represents over three percent of the company's profit for 2012. It calculated the fine based on the gravity of the offense — it says 15 million Windows users in the EU did not see the browser ballot screen as agreed — but also took into account Microsoft's cooperation throughout the investigation. It's not all bad news for Microsoft, though: under EU rules it could've been fined up to ten percent of its total annual turnover for the infraction.

In a statement to the press, Microsoft said it will not be contesting today's fine:

"We take full responsibility for the technical error that caused this problem and have apologized for it. We provided the Commission with a complete and candid assessment of the situation, and we have taken steps to strengthen our software development and other processes to help avoid this mistake – or anything similar – in the future."

Aaron Souppouris contributed to this article

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