How to deny changing and using of a proxy server in internet options using GPO ?
How to use Automatic Configuration Scripts for Proxy Settings (NG 1000, NG 5000, NG 8000, proxy.pac configuration)
batch file - How to toggle 'Use Automatic Configuration script' checkbox in IE settings without clearing the proxy URL? - Stack Overflow
Is it possible to change the automatic configuration script address in the LAN settings of Internet Explorer 8 with the help of a script? - Stack Overflow
The case of proxies and ConfigMgr - An inside view - Microsoft Community Hub
Configuring Proxy Settings via GPO on Windows – TheITBros