Microsoft’s security software modifies HOSTS file

Windows 8, set for release on 26 October, automatically deletes entries in the HOSTS file for specific domains. Try, for example, to prevent attempts to access Facebook.com, Twitter.com or ad servers such as ad.doubleclick.net by rerouting them to 127.0.0.1 by adding entries to the HOSTS file and the relevant entries will soon disappear from the HOSTS file as if by magic, leaving nothing but an empty line. The effect does not occur for other domains, such as The H’s sister site heise.de, however.