Do Not Track (DNT) 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.
In May, Microsoft announced that DNT would be switched on by default for IE10. That stance has not changed - if users take no action, the feature will be enabled - but today the company's chief privacy officer noted that customers can modify the setting if they want.
Setting choices after installation but before software runs is often described as a "first-run" option.
"DNT will be enabled in the 'Express Settings' portion of the Windows 8 set-up experience," Brendon Lynch, Microsoft's chief privacy officer, said in a Tuesday post to a company blog. "There, customers will also be given a 'Customise' option, allowing them to easily switch DNT off if they'd like."
Like earlier editions of the operating system, Windows 8 will offer users alternatives when they first run the software. The Express option accepts the defaults Microsoft has set, including DNT, and is assumed if the user does nothing but proceed with the setup.
Customise lets users modify the default settings before running Windows 8 for the first time. "By using the Customise approach, users will be able to independently turn on and off a number of settings, including the setting for the DNT signal," Lynch promised.
When the user allows Express to complete the Windows 8 setup, they will see what Lynch called a "prominent notice" that tells them IE10 will have DNT switched on.
"Microsoft keeps Do Not Track by default in Win[dows] 8 and IE10, but makes it a first-run option. Hard to argue with that," said Jonathan Mayer in a Tuesday tweet.
Mayer, a researcher at Stanford's Center for Internet and Society (CIS), is one of two Stanford students who devised the HTTP header concept used by browsers to signal a user's DNT decision. He is also active in discussions by the Worldwide Web Consortium (W3C) standards-setting group to finalise DNT's implementation.
In the past, rivals have complained about how Microsoft structures its Express settings, and have claimed that few users select the Customise alternative.
Lynch said feedback drove Microsoft to spell out how IE10 will handle DNT.
"Since [May], we have conducted additional consumer research that confirmed strong support for our 'consumer-privacy-first' approach to DNT," claimed Lynch. "We have also discussed our point of view with many interested parties, who want to learn more about how our customers will first experience and control the DNT setting in IE."
It's clear there are "interested parties" in Microsoft's unilateral decision to turn on DNT.
In June, for example, European regulators urged the W3C to let Microsoft set DNT as on in IE10, even though the standards body leaned toward requiring users to explicitly making a choice.
At that time, Robert Madelin, who heads the European Commission's Information Society and Media Directorate-General, told the W3C that it was enough that users be informed of the default DNT setting and given the opportunity to change it.
Madelin also suggested that a first-run option, like the one Microsoft has adopted, would be appropriate and acceptable to EU officials.
In an interview two months ago with Computerworld, Mayer said at least two other browser vendors were interested in also pushing DNT through a first-run option. He declined to name the browser makers.
Online advertisers have balked at browsers that turn on DNT without asking users, essentially hoping that the standard will not be widely adopted if the signal must be manually switched on.
IE10 will also be available to Windows 7 users, but the process will be different for them, said Lynch. "Windows 7 customers using IE10 will receive prominent notice that DNT is turned on in their new browser, together with a link providing more information about the setting," he said.
Lynch's description could be read as meaning that there will be no first-run option when Windows 7 customers upgrade to the new browser. Microsoft was not immediately able to clarify what DNT choices Windows 7 users will see when they upgrade.
Microsoft has declined to disclose its release plans for IE10 on Windows 7.
Windows 8 - and thus its version of IE10 - will go on sale 26 October.
While Microsoft and the European Commission may see eye-to-eye on DNT, they are at loggerheads on other browser issues.
Last month, the Commission's top antitrust regulator threatened Microsoft with massive fines after the US firm failed to offer 28 million European customers a choice of browsers.
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.