European regulators have urged an Internet standards-setting body to let Microsoft set users' preferences for the "Do Not Track" privacy feature in the upcoming Internet Explorer 10 (IE10).

But the European Commission also asked the Worldwide Web Consortium (W3C) to require browser makers to present Do Not Track (DNT) options to users when they first install or run a browser, and allow them to change the default.

"The standard should foresee that at the install or first use of the browser the owner should be informed of the importance of their DNT choice, told of the default setting and prompted or allowed to change that setting," Robert Madelin, who heads the European Commission's Information Society and Media Directorate-General, said in a Thursday letter (download PDF) to the W3C.

Madelin's suggestion was the Commission's first public reaction to Microsoft's surprise announcement last month that IE10 will have DNT switched on by default.

On May 31, the same day that it released Windows 8 Release Preview, Microsoft's chief privacy officer said that IE10, the browser bundled with Windows 8 and its tablet offshoot Windows RT, would have DNT on by default because the company "believe[s] in people first."

The W3C, however, has opposed Microsoft's move.

In a draft of the standard published shortly after Microsoft's announcement, the W3C group working on DNT said users must express their preference, and that a browser maker could not do it for them.

That meant if Microsoft did not change its mind, or if the W3C did not back down, Microsoft would not be able to claim it supports the standard. Some in the W3C group, primarily online advertisers, wanted even harsher anti-Microsoft language in the standard that would let websites ignore IE10's DNT request because users had not been forced to make the choice themselves.

Mozilla, the maker of Firefox, has backed the idea that only users can turn on DNT.

Do Not Track is a browser feature that signals whether a user wants online advertisers and websites to track his or her movements. All five major browsers -- Chrome, Firefox, Internet Explorer, Opera and Safari -- can send a DNT signal.

Madelin said that IE10's on-by-default shouldn't be an issue.

"It is not the Commission's understanding that user agents' factory or default setting necessarily determine or distort owner choice," said Madelin. "The specification need not therefore seek to determine the factory setting and should not do so, because to intervene on this point could distort the market."

Some pundits have argued that Microsoft set DNT on by default as a way to separate IE10 from rivals, while others have speculated that the move was an attack against Google, which makes the bulk of its revenue from targeting ads that rely on user tracking.