Some anti-virus, anti-sypware/malware, and firewall software lock the Windows Hosts file so no one can edit it (by maintaining an open file-handle with no write share permissions on this file).
The file is – C:\Windows\System32\drivers\etc\hosts The most common Hosts file locker is Spy Bot Search & Destroy.
Anti virus and anti-malware programs are installed in the computer to secure the computer from malware and viruses .
After installation, these software need to update themselves, because without regular update of the virus detection file, security will be compromised.
Others can be: Zone Alarm, Hosts Man, Win Partol, Spyware Blaster, Ad-Aware, etc.
This can be problematic for users with no internet connection.Spybot Search & Destroy (aka Spybot) is a popular proprietary spyware, adware, and malware removal program compatible with Microsoft Windows 95 computers and later.It protects the computer from malicious software while online and scans the computer hard disk, RAM, and external media for malicious files in order to remove them.are bundled with adware and spyware, and the user downloading and installing the application may not even be aware that adware and spyware is being installed.In spite of our best efforts in user education asking our users to be careful while surfing the web and to not install such applications, it has gotten to the point that numerous client machines on the network have enough adware and spyware installed to have a significant negative impact on the performance and even usability of the machine.