Set Proxy Server with Group Policy

You can set the Internet Explorer Proxy settings via Group Policy. There are two methods in which you may want to set proxy settings

Disabling Internet Access

Using the techniques described above you can effectively disable internet access for a targeted group of users and/or computers. All you have to do is set the proxy server to 127.0.0.1 which sets the local device as the proxy server and thus prevents URL's from resolving correctly.

Warnings

The process outlined above does not prevent users from accessing websites via IP address. If you require this sort of thing a dedicated proxy server such as Category:Squid Squid would be more appropriate.

Reference

http://www.smart-x.com/?categoryid=171&articleid=149 http://www.tomshardware.com/forum/221139-46-make-proxy-settings-machine-rather-user http://community.spiceworks.com/topic/33803