Keeping browsing experience in users’ hands | Microsoft Malware Protection Center
To address these and to keep the intent of our policy, we’re updating our Adware objective criteria to require that programs that create advertisements in browsers must only use the browsers’ supported extensibility model for installation, execution, disabling, and removal.
The choice and control belong to the users, and we are determined to protect that.
We encourage developers in the ecosystem to comply with the new criteria. We are providing an ample notification period for them to work with us as they fix their programs to become compliant. Programs that will fail to comply will be detected and removed.
Enforcement starts on March 31, 2016.