Microsoft had agreed to show Windows users a browser ballot as part of a settlement it struck with the Commission in late 2009.
The Commission is also reportedly investigating charges that Microsoft has blocked rivals from harnessing the power of Windows 8 for their browsers.
Gregg Keizer covers Microsoft, security issues, Apple, Web browsers and general technology breaking news for Computerworld. Follow Gregg on Twitter at @gkeizer, on Google+ or subscribe to Gregg's RSS feed. His email address is firstname.lastname@example.org.
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