Starting at the end of July, Microsoft has begun detecting HOSTS files that block Windows 10 telemetry servers as a ‘Severe’ security risk.

The HOSTS file is a text file located at C:Windowssystem32driveretcHOSTS and can only be edited by a program with Administrator privileges.

This file is used to resolve hostnames to IP addresses without using the Domain Name System (DNS).

This file is commonly used to block a computer from accessing a remote site by assigning host to the 127.0.0.1 or 0.0.0.0 IP address.

For example, if you add the following line to the Windows HOSTS file, it will