Redmond published a new specification on Wednesday, which now requires users to turn on the anti-behavioral tracking feature. In other words, it is no longer the default setting and IE 10 will not comply with the official Do Not Track spec, Ars Technica reports.
Do Not Track does not block cookies, it is merely a browser setting that lets websites know that the user does not wish to be tracked.
However, it is not mandatory and it is up to individual sites and advertising firms to choose whether they will comply with the Do Not Track flag.
It was hoped that most reputable sites would take up the initiative, which now seems to be faltering.
Microsoft's announcement will only serve to undermine Do Not Track further and some researchers and punters believe the concept could be dead on arrival.