Assuming those user accounts do not or can not install alternate web
browsers and file swapping programs you can logon as the user, open Internet
Explorer and go to tools/internet options/connections - lan settings. Select
use proxy server and enter 127.0.0.1. Then open Local Group Policy via
gpedit.msc and go to user configuration/administrative templates/Windows
components/Internet Explorer - internet control panel and enable the setting
for "disable the connections page". This will disable access to connections
page for all users including yourself though you as an administrator can
change that setting to disabled if you need access to it and then enable it
again when done. Be sure to test it out to see if it works or not. ---
Steve