By clicking the "Use express settings" button to continue, the user accepts Microsoft's defaults, including DNT as switched on.

Users can, as Lynch promised, turn off DNT by choosing the Customize option. There, DNT is listed on the second of two screens, and can be switched off by toggling "Send a Do Not Track request to websites you visit with Internet Explorer."

Windows 8 users can change their minds at any time on DNT, and alter the setting through IE10's Internet Options dialog box. The DNT option is listed as "Always send Do Not Track header" under the Advanced tab of that dialog.

DNT signals whether a user wants online advertisers and websites to track his or her movements. All five major browsers -- Chrome, Firefox, IE, Opera and Safari -- can send a DNT signal, but only IE10 has it on by default.

(Apple's Safari switches DNT on when users surf the Web in private browsing mode.)